Yes, I came back tonight and it happened again! I think it does have something to do with other players coming in the room. I noticed at least this much before so I don't invite people in the room any more when I'm Forging. When I want to show someone my work I save it, end game then invite them in. After starting up a new game giving a tour I take notes on ideas and changes, making sure not to do any at the time. Then I end the game again and part ways into my own room to continue editing. This seems to preventative. Also, when this [i]revert[/i] happens the file must be corrupt or something because it uploads to my file share but stays at 100% and will not confirm completion. A few days latter I can only assume it gets cleaned up by some script for my file share slot become available once again. I found this out by trying to have a friend download it and see if the problem was the same. Only to be stopped at the upload. I have no idea if anyone at Bungie knows about this or if a one of the Bungie.net moderators have seen others posts on this specific Forge topic and passed the word along. But I would think this would be a concern and maybe a possible fix especially since the Bungie Halo:Reach Forgetacular Contest is now underway. There's going to be a lot of people showing maps to their friends only to be extremely disappointed the next day when they come back to continue their creativity.