Check in Settings if you're using Local or Web images. Sometimes the web host I use goes down, if you're using web. Local should work fine is the index.html is in the same folder holding /img/ bit admittedly I've never tested this on Linux.
I found out shortly after I wrote that and had been playing since! I hope you are able to make more than only one image for each scene, before and after a creampie for example, though I understand that might be difficult :)
