Right at the moment when a map I'm working on is about to finish loading, the game freezes. There aren't any munging issues, and there weren't any game crashing problems in the error log, just the usual "InVehicle" stuff. The only thing I can think of it being is that I've hit the object limit, but I don't know how to check for sure if I have or not. Is this the kind of problem that happens when the limit is hit, and is there a way to identify how many objects I have (besides counting them one by one in ZeroEditor )?

If you open your lyr or wld files in NotePad++ you can get an object count by clicking ctrl+f and type the word "object" (without quotes), then click on "Count" in that window and it'll give you the # that corresponds to how many times "object" was found in that file.
Thanks to MasterSaitek009 for this info.

Thanks! I hadn't downloaded Notepad++ until now, but it looks like a great improvement over the normal Notepad program.