When you're working on a large project, it's always a good idea (actuallty, it's probably extremely important!) to make multiple saves of your program as you increase the version number. For example, you save file GAME_VO.OO1, and then after a while save GAME_VO.OO2. If you happen to save over a version, you'll only have to go back one version and pick up from there. Also, I think SmileBASIC...
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