If you are able to run the toolset but NOT able to build with tile sets and cannot activate an Occlusion grid: try this fix.
[TLDR Summary: The program must be run with windows XP compatibility service pack 2 ]
-Create a shortcut to Nwn2toolset.exe and place it on your desktop (this is a required step!).
-In your taskbar search type “program compatibility troubleshooter” and launch the program it finds which should say something like "run programs made for previous version of windows (ignore web results).
-The program will ask to populate a list of applications by searching your computer: Let it do so.
-On the list it populates : select the toolset shortcut you created.
-Follow the prompts (select the top option)
-When asked select “test program” it should Launch the toolset on it’s own.
-Create a new interior area in the toolset , toggle the Occlusion grind ON (top left), and select Tile sets (bottom right),
-select ant tile from the list just above and place it on the area, repeat this process a few times.
-if it works , go back to the troubleshooter and tell it, that everything worked, follow the prompts and it will save the needed settings to launch the toolset properly.
-Running the program as admin is recommended.
Summary: The program must be run with windows XP compatibility service pack 2