Hi, AdrianoGolob!
Welcome here!
AI in war2 cannot control units if they become clinched between obstacles or between each others (the main problem is peons clinched near the gold mine). Then computer just stops and do nothing.
That can not be fixed, only bypassed: try to play maps with open spaces between gold and TH. Try to edit the map, to deny building near gold (to prevent comp to build farms or w/e between gold and TH, that is also possible).
If you download war2combat, you can install it with "violent AI" component instead of campaign (deselected by default, you should select it manually while installing), then you will see AIE subfolder in maps folder. These maps are fixed a little bit to bypass some stupid ai behavior like opportunity of building between gold mine and TH.
Also these maps use much more effective AI than the default one when you use maps from subfolder AIE. Big job have been made in AIE for those who want to play vs computer players.