Campaign Mode crashes in Red Baron 3D-What's wrong?

Couldn't find a solution to this anywhere in the forums. I am running 2 versions of Red Baron 3D(it's true, I still play it), one stock, and one running the Full Canvas Jacket Superpatch. What's going on is that at one point, when I was running the Full Canvas Jacket patched version(I installed the fully stock one several weeks back), I had returned to the main Campaign Mode menu after having a look in the plane Paint Shop, then, when it went back there, the game black-screened on me, and gave me the error message(that Oh-so-annoying message):

Red Baron II Singleplayer has encountered a problem and needs to close. We are sorry for the inconvenience.

Here's the thing: it was working before, but now, it won't even get past the main Campaign Mode menu. It does the same in the fully stock version. I hadn't registered a pilot, so I decided to do that today, and guess what, it did the same thing as the Full Canvas Jacket patched one. Did the patch break something in any way? It was fully functional before I applied the patch and a certain while after that. What has gone wrong?

EDIT: Seems like the Full Canvas Jacket patched version is working now(I tried applying the Western Front patch to get extra planes). It still does it in the stock version.