misscrabtree456: Gog has a nice rollback "feature" that lets you go back to an earlier version of a game if a patch messes up the game. Sounds nice. It's not. All ti is, is a start over feature. I can do that myself. I don't need Gog screwing me out of 100 hrs of progress with saying so. I can't do that all on my own. How stupid can you get.
As I understand it from some threads in other forums, Hello Games made some changes to the saved games file format in 1.58. As a result, 1.57 won't recognize a 1.58 save as valid and so will start over.
You can (and should) make your own periodic backups of the saved games directory. If you had made a checkpoint backup before choosing to install 1.58, then you could drop those saves into the appropriate directory after rolling back to 1.57 and be on your way.
Unlike some other platforms, GoG lets the end user decide whether/when to install a patch. Given how the recent patches have gone, grabbing a backup of the saved games before opting for any of the NMS patches is A Good Idea.
You should still be able to recover and run 1.58 if you made a backup prior to rolling back to 1.57. Granted, 1.58 has some real issues (WTF was HG thinking to release it in that state???) but they're not game killing, just annoying as hell. I don't *think* that NMS overwrites older saves (not 100% sure tho) so going back to 1.58 even without using a backup may be possible.