As for the feedback, I don't know where to find the files on my drive. Any ideas?
For me they're in C:\Users\[MyUser]\AppData\Local\Larian Studios\Baldur's Gate 3\PlayerProfiles\Public\Savegames\Story
Each save is in a folder with the savegame and a thumbnail. I've seen some posters here mention that it's helpful if you zip and send the whole folder, including the thumbnail, rather than just the save.