I think you guys are looking on the wrong 'level'. Both 1.51 and 1.7 got AI value settings defined in every map. Those value settings between the 2 versions are a bit different (sometimes to low or to high) but still he does not execute them at all and simple ignore them. Example the setting/value attack when all creatures are lvl X, this one is in 1.7 ignored dunno about 1.51. Same goes for dropping creatures near a enemy.
The settings and there values are there, but simply ignored.
DK2 got a different loader for each "type" of map:
- Official campaign levels: Loader A
- Self made levels played as single player mode: Loader B
- Self made levels played as campaign level: Leader B
- Self made levels played as MPD: Loader B
- Self made levels played as skirmish: Loader C
Loader C is the best in 1.7, it does follow "attack when all creatures are lvl X" (and thus using the combat pit) and dropping creatures better near a enemy.
A simple test is pick a campaign level, save it but don't change anything and play it as a campaign level or as a single player level and most settings are then simply ignored. Play it as skirmish and the AI is better and follow all settings.
Maybe its the editor itself that fucks things up i dunno.
The game clearly distinguish what loader it has to use. If you can change this, that it will always use Loader C instead of the others, then you got a way better AI in every map