Welcome to the Org, Krondor.

You would probably do better to post this in the Alchemist Lab, that's where the MTW modders hang out, although they sometimes drop by here.
https://forums.totalwar.org/vb/forumdisplay.php?f=18
I'm sure you can get some help there, you probably won't even have to pay them.

You can also check out the Repository, there are some threads in there for creating maps:
https://forums.totalwar.org/vb/forumdisplay.php?f=39
there is a LukMap thread in there that may help:
https://forums.totalwar.org/vb/showthread.php?t=30803

Just noticed your video card, there is a known issue with the newer nVidia drivers, it's also possible that this could be causing your problem. Setting your anti-aliasing to 2 might solve this, as described in this thread:
https://forums.totalwar.org/vb/showt...hp?t=64977#top
If the standard MTW campaigns doesn't work on your machine, this might be the problem.

Can't help you anymore than that, I just play, I don't have time to Mod. Good Luck! (and nice system )