diff --git a/GameSettings.cpp b/GameSettings.cpp
index 88b2b465..4ffe5e01 100644
--- a/GameSettings.cpp
+++ b/GameSettings.cpp
@@ -3123,6 +3123,16 @@ void LoadItemSettings()
 	gItemSettings.fRecoilXModifierGun[GUN_SHOTGUN]					= iniReader.ReadFloat  ("Weapon Settings","RECOILX_SHOTGUN_MODIFIER", 1.0f, 0.1f, 5.0f);
 	gItemSettings.fRecoilYModifierGun[GUN_SHOTGUN]					= iniReader.ReadFloat  ("Weapon Settings","RECOILY_SHOTGUN_MODIFIER", 1.0f, 0.1f, 5.0f);
 
+	gItemSettings.usJamDamageThresholdGun[NOT_GUN]					= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_NOT_GUN", 0, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_PISTOL]				= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_PISTOL", 50, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_M_PISTOL]				= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_MP", 75, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_SMG]					= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_SMG", 70, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_RIFLE]				= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_RIFLE", 40, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_SN_RIFLE]				= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_SNIPER", 45, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_AS_RIFLE]				= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_AR", 65, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_LMG]					= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_LMG", 60, 0, 100 );
+	gItemSettings.usJamDamageThresholdGun[GUN_SHOTGUN]				= iniReader.ReadInteger("Weapon Settings","JAM_DAMAGE_THRESHOLD_SHOTGUN", 30, 0, 100 );
+	
 	// -------------- ARMOR MODIFIERS ----------------
 	gItemSettings.fCamoLBEoverVestModifier							= iniReader.ReadFloat  ("Armor Settings","CAMO_LBE_OVER_VEST_MODIFIER", 0.2f, 0.0f, 1.0f);
 	gItemSettings.fCamoLBEoverPantsModifier							= iniReader.ReadFloat  ("Armor Settings","CAMO_LBE_OVER_PANTS_MODIFIER", 0.2f, 0.0f, 1.0f);
diff --git a/GameSettings.h b/GameSettings.h
index f393daaf..16542fb7 100644
--- a/GameSettings.h
+++ b/GameSettings.h
@@ -2355,6 +2355,8 @@ typedef struct
 	// Recoil modifiers
 	FLOAT fRecoilXModifierGun[GUN_TYPES_MAX];
 	FLOAT fRecoilYModifierGun[GUN_TYPES_MAX];
+	// Jam damage thresholds
+	UINT16 usJamDamageThresholdGun[GUN_TYPES_MAX];
 
 	// -------------- ARMOR MODIFIERS ----------------
 	FLOAT fCamoLBEoverVestModifier;
diff --git a/GameVersion.cpp b/GameVersion.cpp
index 7a7b6b61..169601ee 100644
--- a/GameVersion.cpp
+++ b/GameVersion.cpp
@@ -15,9 +15,9 @@
 #ifdef JA2EDITOR
 	
 	#ifdef JA2UB
-		CHAR16 zVersionLabel[256]		= { L"Unfinished Business - Map Editor v1.13.8364 (Development Build)" }; 
+		CHAR16 zVersionLabel[256]		= { L"Unfinished Business - Map Editor v1.13.8370 (Development Build)" }; 
 	#else
-		CHAR16 zVersionLabel[256]		= { L"Map Editor v1.13.8364 (Development Build)" }; 
+		CHAR16 zVersionLabel[256]		= { L"Map Editor v1.13.8370 (Development Build)" }; 
 	#endif
 
 // ------------------------------
@@ -27,11 +27,11 @@
 
 	//DEBUG BUILD VERSION	
 	#ifdef JA2UB
-		CHAR16 zVersionLabel[256]		= { L"Debug: Unfinished Business - v1.13.8364 (Development Build)" }; 
+		CHAR16 zVersionLabel[256]		= { L"Debug: Unfinished Business - v1.13.8370 (Development Build)" }; 
 	#elif defined (JA113DEMO)
-		CHAR16 zVersionLabel[256]		= { L"Debug: JA2 Demo - v1.13.8364 (Development Build)" }; 
+		CHAR16 zVersionLabel[256]		= { L"Debug: JA2 Demo - v1.13.8370 (Development Build)" }; 
 	#else
-		CHAR16 zVersionLabel[256]		= { L"Debug: v1.13.8364 (Development Build)" }; 
+		CHAR16 zVersionLabel[256]		= { L"Debug: v1.13.8370 (Development Build)" }; 
 	#endif
 
 #elif defined CRIPPLED_VERSION
@@ -46,16 +46,16 @@
 
 	//RELEASE BUILD VERSION	
 	#ifdef JA2UB
-		CHAR16		zVersionLabel[256]		= { L"Release Unfinished Business - v1.13.8364 (Development Build)" };
+		CHAR16		zVersionLabel[256]		= { L"Release Unfinished Business - v1.13.8370 (Development Build)" };
 	#elif defined (JA113DEMO)
-		CHAR16		zVersionLabel[256]		= { L"Release JA2 Demo - v1.13.8364 (Development Build)" };
+		CHAR16		zVersionLabel[256]		= { L"Release JA2 Demo - v1.13.8370 (Development Build)" };
 	#else
-		CHAR16		zVersionLabel[256]		= { L"Release v1.13.8364 (Development Build)" };
+		CHAR16		zVersionLabel[256]		= { L"Release v1.13.8370 (Development Build)" };
 	#endif
 
 #endif
 										
-CHAR8		czVersionNumber[16]	= { "Build 17.01.14" };		//YY.MM.DD
+CHAR8		czVersionNumber[16]	= { "Build 17.01.22" };		//YY.MM.DD
 CHAR16		zTrackingNumber[16]	= { L"Z" };
 	
 // SAVE_GAME_VERSION is defined in header, change it there
diff --git a/Strategic/Assignments.cpp b/Strategic/Assignments.cpp
index b8f23b84..7943135e 100644
--- a/Strategic/Assignments.cpp
+++ b/Strategic/Assignments.cpp
@@ -3029,27 +3029,18 @@ UINT8 CalculateCleaningPointsForRepairman(SOLDIERTYPE *pSoldier, UINT16 *pusMaxP
 	}
 
 	// calculate effective repair rate (adjusted for drugs, alcohol, etc.)
-	usCleaningPts = (UINT16) ((EffectiveMechanical( pSoldier ) * EffectiveDexterity( pSoldier, FALSE ) * (100 + ( 5 * EffectiveExpLevel( pSoldier) ) )) / ( gGameExternalOptions.ubCleaningRateDivisor * gGameExternalOptions.ubAssignmentUnitsPerDay ));
+	usCleaningPts = (UINT32)( (( EffectiveMechanical( pSoldier ) + 3 * EffectiveDexterity( pSoldier, FALSE ) + 50 * EffectiveExpLevel( pSoldier) ) * 1000 ) / ( gGameExternalOptions.ubCleaningRateDivisor * gGameExternalOptions.ubAssignmentUnitsPerDay ) );
 
 	// calculate normal repair rate - what it would be if his stats were "normal" (ignoring drugs, fatigue, equipment condition)
 	// and equipment was not a hindrance
 	INT16 mechanical = (pSoldier->stats.bMechanical * (100 + pSoldier->GetBackgroundValue( BG_MECHANICAL ))) / 100;
 	INT16 dexterity  = (pSoldier->stats.bDexterity * (100 + pSoldier->GetBackgroundValue( BG_DEXTERITY ))) / 100;
-	*pusMaxPts = (mechanical * dexterity * (100 + (5 * pSoldier->stats.bExpLevel))) / (gGameExternalOptions.ubCleaningRateDivisor * gGameExternalOptions.ubAssignmentUnitsPerDay);
+	*pusMaxPts = ( ( mechanical + 3 * dexterity + 50 * pSoldier->stats.bExpLevel ) * 1000 ) / (gGameExternalOptions.ubCleaningRateDivisor * gGameExternalOptions.ubAssignmentUnitsPerDay);
 
 	// SANDRO - Technician trait gives a good bonus to repair items
 	// we also use that for cleaning guns
 	if ( gGameOptions.fNewTraitSystem )
 	{
-		usCleaningPts = usCleaningPts * (100 + gSkillTraitValues.bSpeedModifierRepairing) / 100;
-		*pusMaxPts = *pusMaxPts * (100 + gSkillTraitValues.bSpeedModifierRepairing) / 100;
-
-		if ( HAS_SKILL_TRAIT( pSoldier, TECHNICIAN_NT ) )
-		{
-			usCleaningPts += usCleaningPts * gSkillTraitValues.usTERepairSpeedBonus * (NUM_SKILL_TRAITS( pSoldier, TECHNICIAN_NT )) / 100;
-			*pusMaxPts += *pusMaxPts * gSkillTraitValues.usTERepairSpeedBonus * (NUM_SKILL_TRAITS( pSoldier, TECHNICIAN_NT )) / 100;
-		}
-
 		// Penalty for aggressive people
 		if ( DoesMercHavePersonality( pSoldier, CHAR_TRAIT_AGGRESSIVE ) )
 		{	
@@ -3071,8 +3062,6 @@ UINT8 CalculateCleaningPointsForRepairman(SOLDIERTYPE *pSoldier, UINT16 *pusMaxP
 	if ( gGameOptions.fFoodSystem )
 		ReducePointsForHunger( pSoldier, &usCleaningPts );
 
-	usKitPts = CleaningKitPoints( pSoldier );
-
 	// return current cleaning pts
 	return(( UINT8 )usCleaningPts);
 }
diff --git a/Tactical/Weapons.cpp b/Tactical/Weapons.cpp
index 52d18d4f..baf046bb 100644
--- a/Tactical/Weapons.cpp
+++ b/Tactical/Weapons.cpp
@@ -27,6 +27,7 @@
 	#include "tile animation.h"
 	#include "Dialogue Control.h"
 	#include "SkillCheck.h"
+	#include "Render Fun.h"
 	#include "explosion control.h"
 	#include "Quests.h"
 	#include "Physics.h"
@@ -1334,15 +1335,18 @@ BOOLEAN CheckForGunJam( SOLDIERTYPE * pSoldier )
 					// Deduct AMMO! 
 					DeductAmmo( pSoldier, pSoldier->ubAttackingHand );
 
-					// silversurfer: Our gun can now take damage when it jams
-					if ( PreRandom( 100 ) < (90 - condition + (Item[(*pObj).usItem].usDamageChance / 2.0f)) )
+					// silversurfer: Our gun can now take damage when it jams but only if the gun is below the jam damage threshold
+					if ( condition < gItemSettings.usJamDamageThresholdGun[Weapon[(*pObj).usItem].ubWeaponType] )
 					{
-						// damage depends on gun status. The better the status the less damage it takes. Limit it to max 5 or it can be frustrating for the player.
-						UINT32 uiJamDamage = __min( 5, PreRandom( __max( 0, (UINT32)((90 - condition) / 2.0f ) ) ));
-						if ( uiJamDamage > 0 )
+						if ( PreRandom( 100 ) < ( Item[(*pObj).usItem].usDamageChance + ( 100 - condition ) / 5 ) )
 						{
-							(*pObj)[0]->data.objectStatus -= __min( uiJamDamage, (*pObj)[0]->data.objectStatus );
-							(*pObj)[0]->data.sRepairThreshold -= __min( uiJamDamage, (*pObj)[0]->data.sRepairThreshold );
+							// damage depends on gun status. The better the status the less damage it takes. Leave a chance for 0 damage.
+							UINT32 uiJamDamage = __max( 0, PreRandom( 5 - UINT32(condition / 30.0f) ) );
+							if ( uiJamDamage > 0 )
+							{
+								(*pObj)[0]->data.objectStatus -= __min( uiJamDamage, (*pObj)[0]->data.objectStatus );
+								(*pObj)[0]->data.sRepairThreshold -= __min( uiJamDamage, (*pObj)[0]->data.sRepairThreshold );
+							}
 						}
 					}
 				 
@@ -2348,6 +2352,9 @@ BOOLEAN UseGunNCTH( SOLDIERTYPE *pSoldier , INT32 sTargetGridNo )
 	else if ( ubSectorId >= 0 && ubSectorId < 256  )
 	{
 		sectormod = SectorExternalData[ubSectorId][gbWorldSectorZ].usNaturalDirt;
+		// half dirt value if we are in a building (room)
+		if ( InARoom( pSoldier->sGridNo, NULL ) )
+			sectormod /= 2;
 	}
 
 	// the current sector determines how likely it is that dirt increases
@@ -3047,6 +3054,9 @@ BOOLEAN UseGun( SOLDIERTYPE *pSoldier , INT32 sTargetGridNo )
 	else if ( ubSectorId >= 0 && ubSectorId < 256  )
 	{
 		sectormod = SectorExternalData[ubSectorId][gbWorldSectorZ].usNaturalDirt;
+		// half dirt value if we are in a building (room)
+		if ( InARoom( pSoldier->sGridNo, NULL ) )
+			sectormod /= 2;
 	}
 
 	// the current sector determines how likely it is that dirt increases