adjustments to ExtraItems

- currently only works on ground-level
- adjusted readme to inform that it doesn't work at  underground levels
- replaced the former example file that happened to be underground with one at groundlevel

gamedir/Data-1.13/TableData/Map/ExtraItems/A2_0_ExtraItems_Experienced.xml

@@ -7,7 +7,7 @@
       <uiIndex>201</uiIndex>
       <quantity>2</quantity>
       <condition>100</condition>
-      <gridno>14469</gridno>
+      <gridno>18174</gridno>
       <visible>1</visible>
    </Item>
 </ExtraItems>

gamedir/Data-1.13/TableData/Map/ExtraItems/A2_0_ExtraItems_Expert.xml

@@ -7,7 +7,7 @@
       <uiIndex>205</uiIndex>
       <quantity>2</quantity>
       <condition>100</condition>
-      <gridno>14469</gridno>
+      <gridno>18174</gridno>
       <visible>1</visible>
    </Item>
 </ExtraItems>

gamedir/Data-1.13/TableData/Map/ExtraItems/A2_0_ExtraItems_Insane.xml

@@ -7,7 +7,7 @@
       <uiIndex>257</uiIndex>
       <quantity>1</quantity>
       <condition>100</condition>
-      <gridno>14469</gridno>
+      <gridno>18174</gridno>
       <visible>1</visible>
    </Item>
 </ExtraItems>

gamedir/Data-1.13/TableData/Map/ExtraItems/A2_0_ExtraItems_Novice.xml

@@ -7,14 +7,14 @@
       <uiIndex>201</uiIndex>
       <quantity>2</quantity>
       <condition>100</condition>
-      <gridno>14469</gridno>
+      <gridno>18174</gridno>
       <visible>1</visible>
    </Item>
    <Item>
       <uiIndex>1029</uiIndex>
       <quantity>1</quantity>
       <condition>100</condition>
-      <gridno>14469</gridno>
+      <gridno>18174</gridno>
       <visible>1</visible>
    </Item>
 </ExtraItems>

gamedir/Data-1.13/TableData/Map/ExtraItems/Extra Sector Items readme.txt

@@ -1,6 +1,5 @@
 This is an old 1.13 Feature which seems to be hidden for Modders long time.
 This feature has been reworked by Headrock
-
 (edit: and since it got lost again, now revived)
 
 -------------------------
@@ -11,7 +10,9 @@ XML filename format:
 
 Examples:
 \TableData\Map\ExtraItems\A9_0_ExtraItems_Novice.xml	-> for entering the A9 surface sector (Omerta) when playing novice difficulty.
-\TableData\Map\ExtraItems\D13_1_ExtraItems_Expert.xml	-> for entering the first level of the Drassen Mine on Expert difficulty.
+
+(edit: -> underground-levels see [NOTE] below)
+
 
 The following "DifficultyNames" are valid:
 
@@ -64,8 +65,12 @@ XML notes:
 
 - random-items can also be used
 
-- it's happening in realtime
+- As I understand, that's happening in realtime. So it's probably advised to not overdo it
+
+  It's meant to add a few goodies (differing on which difficulty level we're at), not to replace the item-placement via mapeditor
 
 - added a few example files to portrait the idea
 
+[NOTE: It's a bummer, but it doesn't seem to work with underground-levels. That might be an old issue, at least all examples I found, even going back to v4870, also only had ground-level in use as well. So, for the time being, it only works on ground-level (using only 0 for level, like in "A9_0_ExtraItems_Novice.xml")]	
+
 (edited 22.08.2023)