Thanks, but I think you're experiencing something other than what I was. I am aware of the blinking frame, of course! But, that wasn't a fix in my case; as I mentioned in my post, I had tried replacing all images (including the blinking frame) and it only "fixed" things until the next time I opened the program.
However—the issue I was having has been addressed since I posted it. It should be fixed in the current version. So, if you're seeing a flashing effect, it might be a new bug. I believe normally, the program shouldn't try to use a blinking frame at all if none is provided.