Looking at it I would reckon we could go down a number of paths to see what the actual problem is.
From the looks of it my first guess would be the tileset textures are not just installed correctly, which would be why you can't click on the ground with AoE. As well as it's quite frankly, a very odd issue.
So i'd try these things just to see if it can be solved that way.
- See if you can find tileset overrides, think we have a couple on our forum but any from the new nwnvault would do (Specifically get the ones that cover the Underdark)
- Delete the Amia Haks and redownload/install them since if memory serves, we use some custom Tilesets.
- Reinstall NWN with the disk
- Sob..
Hope it helps
Edit: Think getting it from GoG would certainly help, but being the person I am i like knowing what the answer to a problem is
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