Thanks for that advice. But, I haven’t had luck with it, so far.
I have tried opening a minimal module and then testing. For example, the screenshot below
is from the “CEP - Starter 265” module that comes with CEP. It has only one area. I opened it in the Toolset, then opened the game, did nothing in the game (didn’t open a module, didn’t go to a PW, etc.) and closed the game. When I go back to the Toolset, the above is what I see. As you can see, the area list has only the one area and it is completely empty (not even the headers for Merchants, Encounters, etc.).
I tried the same thing with a (non-CEP) blank module with one area and painted a single encounter and one chest in it. I saved the module, opened NWN, closed NWN, and now the Toolset has been nonresponsive for about two minutes.
I haven’t changed hardware in a long time. I think that the last time I updated display drivers was actually after I first started noticing this Toolset issue.
Looking at changes to the the C++ runtime libraries is a good thought. Unfortunately, in the middle of August, I upgraded my Windows 7 machine to Windows 10 and that spawned a ton of software updates and re-installations, including Microsoft Visual C++ Redistributable for 2013 and 2015 (for both x86 and x64). I have no idea which of those might be connected to this Toolset issue.
I do see (at https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads) that there may be newer files for Visual C++. I don’t know if installing the 2019 packages would be helpful here or not.