I've posted this in bug reports but it's looking like it's probably something to do with my code but I'm am at a loss for what it could be.
If anyone's willing to take a look please do, I am absolutely baffled
If anyone has any ideas of how I could go about debugging this that would be super helpful too.
After some mode debugging I think I've figured out the actual issue. For whatever reason when these two sprites overlap, the game crashes.
I have absolutely no idea why this would be happening, there's no collisions on anything. I have no idea what's happening
So I've got a workaround working, I can't tell you what I'm doing differently, I'm just doing the same things in different places now 
Do you have a source control diff that we can look at to get to the bottom of it?
I've tried adding the changes one at a time, it's something to do with the changes in the levelEditRoom.lua file.
::edit::
After more poking around, this is the smallest change I can make to get it working Github diff
essentially all I did was delete setUpdatesEnabled() and add self:markDirty() the the sprites update function.
weirdly, if I remove these changes from the newest version, it still works 