I've pulled an all nighter to try and get some finishing touches on a game jam game. Part of this involved turning an engine test into some levels. With the lack of a feature that I can use to keep putting down multiples of the same background object I have spent hours hand placing tiles to make a fun and exciting landscape to explore. Now here I am at 5:30 in the morning, wanting to test my level after placing everything (there were around... 750? objects) I press test and load into an utter mess. My character falls through the floor because it's just gone. It's not there. I notice a lot of the tiles are gone and go back into the editor to see whats happened. There I find that not only are they gone in the game they're gone in the editor too. Hours of work has suddenly been wiped away. Yes I should have saved more often. But if theres a chance that the engine can just delete hundreds of objects seemingly at random (the last tiles I've placed were still there, as were the first few, it was just most of them were gone at random) I don't really want to use it?
Can anyone help or suggest anything? I have now missed the deadline of the jam because of this and I am utterly mortified. What a waste of time