Yes this is a good idea!
This was quite a while ago when it happened but I definitely learnt my lesson. The problem was after it was overwritten there was less than 4 hours of the competition left, so not enough time to put something together.
Even if I had enough time though, the initial entry was very rushed and rushed*rushed = bad quality, so I think it was for the best I didn’t end up submitting.
Yes at the time I checked the shadow copy of the whole system with no luck.
I find cloud hosting can be useful but also a hassle sometimes. Using something like dropbox might work.
I guess all 1’s and 0’s are volatile to some extent, no worries this happened a while ago, but I learnt my lesson so it didn’t happen for my BGMC 21 entry!
To anyone else wanting to be even more safe here is a brilliant solution that helped me when having to reset my computer from a system image:
(windows only) A simple and ingenius application called SyncToy which copies all modified files to a set directory (on a secondary backup drive for me).
You can get it here, very easy to setup as well!