I just wrote this comprehensive list of how to do it then realized something. Just use or create another user in windows. I'm gonna leave the whole thing but if you don't understand it all, the other user thing is the safer bet.
I think it stores data in 3 places and I think you need to erase all 3. This can get kind of tricky and dangerous. It requires going into regedit to edit the registry among other things. If doing only one of the steps worked for some people it may be down to security settings or windows versions or something.
**WARNING, IF YOU DON'T UNDERSTAND THESE STEPS, STOP!** You can easily break your computer if you delete the wrong things. But I'm going to try to make a complete list here since lots of people are asking this question on this page.
1 - go to the %appdata% folder (type that in location spot on file explorer). This one can be weird because different versions of windows do it a little differently but you are looking for a folder called "FunTech". may have to go "up" from the directory and look in the directories there (Local, LocalLow, Roaming, etc). Delete the "Funtech" folder.
2 - The actual downloaded game files. Just delete it all and re-decompress or redownload. I don't know where the save files are exactly and haven't looked.
3 - Regedit. Again, don't do this if you don't understand, this part is especially dangerous. Run Regedit and do a search for BitBuddy. you will find some random stuff (recent files etc) but you are looking for a bunch of settings. As long as it is only bitbuddy stuff you should be safe deleting it all.
Good luck and I hope you didn't break your pc.