While it's possible to extract a sim created in game using SimPE, to package that sim to share, you'll need Bodyshop. If you haven't deleted cigen.package in addition to Groups.cache, try that. It's used only by Bodyshop, so if you have one floating around your directory from before you uninstalled and reinstalled, it could be causing a problem.
*makes note to get SimPE*
Thank you, I cant remember if I deleted cigen.package too, I know I deleted the .cache, I'm going to try that now. I'll come back and let you know if it works, THANK YOU!
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Yeah, no luck deleting that cigen file either... I cant believe I killed my bodyshop lol
So even with simPE i'd still need my bodyshop working to package my sim? Shucks...