hello! im new and i have been trying to figure this out for half a decade! no joke! i try to select a different stage but its the same stage every time! and i tried terrain editor! previewed it. and guess what? the stage changed to the exact same default one!:( so if somone could please help me figure out how to choose a different stage i would really appreciate it thank you!

Let's start by answering a few simple questions:

When did you buy your copy of the game?
Which version do you have? For example, does the packaging say "Sold Out" or "Green Pepper", or similar?
Have you tried uninstalling and reinstalling the game?
Does your CD have any scratches or marks on the underside?

Try deleting your ..\data\current.thm file.

Although, a clean reinstall normally resolves this issue.