The Sims 4 legacy Edition stopped working

Since the new update arrived I am having a lot of problems but the main problem is that my Legacy Version is not opening at all which is quite weird because my 64 bit version opens and works correctly (before you ask, I urgently need the Legacy version to create Non CC content) I have tried everything to fix this and nothing has worked and I urgently need this version of the game. I haven't tried uninstalling and reinstalling because I am kind of scared because I heard from people who have had a lot of problems after doing this. my PC is quite old and has Windows 7. Could someone please explain how to uninstall and reinstall the game safely and step by step please. I don't want to lose what I have posted or saved in the gallery and the packs that have been given to me