microsoft .NET framework error

So I was just messing around with the program clicking random stuff and trying to make something without watching any of the tutorials and I clicked on export just to see if I made a game and I got this "microsoft .net framework" error. I think this has to do with something literally outside of NESmaker. Anyway just wanted to show it.

Also I'm getting an infinite popup that says "tileset change detected" and no matter how many times I click YES or NO the window just keeps on popping up again and again.

It's possible if your selection went out of bounds on something or whatever, or you found some dark corner by doing some crazy series of things, this is possible (to get this error). Try just hitting continue, as it's probably something set to a null reference that's looking for a value.

As for tile change detected, did you change a tileset?

The thing is a pretty volatile piece of software. Definitely watch the tutorials to get you started, or things like this are bound to happen

Yeah, I've gotten quite a few framework errors, usually by doing something the program didn't expect me to do, luckily an error doesn't crash the program completely and it continues none the wiser.