FreeGameDev

So whenever I try to change the stats of the level (name, length, background, etc.), the game just quits. Anything I should do?

To rename a level, you should go into the Supertux folder, find the fold that begins with a "." (Sorry, I forgot the folder name) and go into the levels file, from there, go into the level set you are working on, and rename the level from there.

Thanks!

I've never experienced that bug myself, it's the firt time I've ever heard about it. As said before, you can change almost everything in the level file, except the length. If you want to change the length, you also have to fill the tilemaps (background-tm), (interactive-tm) and (foreground-tm) by correstonding count of tiles. Each number stays for one tile and the levels are 15 tiles high. Therefore if you want to extend the length to eg. 210, there should be 3150 numbers in each tilemap. Zero is blank tile.
You should also know that the 0.1.3 editor is outdated, so it's not going to be fixed.

It happens a lot in Windows.

Windows is a vague term, since, you know, what they started to do with that. I personally have tried that editor on several Windows machines and I didn't experienced it anyway. Maybe it's a new feature of Windows 8, I have never tested the editor on Windows 8 or newer.

I have seen it happen on Vista and heard about it happening on 10.

Yeah, I knew that it's a new feature of Windows.
I've tested it myself on one Windows Vista machine, but it worked on it.