Something else you (and anyone else who has a Kotor Tool problem) should do (at the bare minimum) is to always post the version of Kotor Tool you're using. Remember, the more relevant info you post, the easier it is to solve your problem.
No developer likes to play the "How little information can I solve this problem with?" game.
So, a better way to ask for help would be:
"I get an error while trying to load the KotOR II module 851nih. I am using version 1.0.2171.12345
of Kotor Tool and version 1.2005.1010.1
of MapInfo.bfd and have copied the large map (map851nih.map) to the Maps folder inside of the Kotor Tool folder. I used the Extract for Module Editing function to put module's contents into a folder under My Documents\Module Projects\851nih. When I launch the Module editor, choose Open and select that folder, I get this error. (screenshot or EXACT text of error message here)."
This is the level of detail that can get your problem solved ASAP. If the abover versions were actual, I could easily say that version 1.2005.1010.1 of MapInfo.bfd didn't support the map for 851nih.
The idea is to second guess all of the things that might need to be known to solve your problem and post them in one fell swoop. That way, the chances are that you'll get a "next visit from Fred" anwser instead of waiting through several requests and replies of extra info.