I’m glad tilemaps are working for you, if nothing else. I’m not sure what else anyone can do for your tiled sprite rendering issue.
I even went as far as testing with a tiled sprite that would flood available ram due to it’s size, and while preview ran terribly low FPS, it still rendered in both the editor and the preview.
Unless you can reproduce the issue on a different system entirely (in a new project, too), I’m not entirely sure folks could narrow it down for you.
I actually had something like this happen to me last night while i was recording the dev log.
I didnt do anything to them all i did was change to the even sheet and back.
When i finally noticed it, i saved, restarted GDevelop and the Ladder tiles were back where they were suposed to.
Iv had this graphical glitch happen to me before, same solution, turn it off and on.
Video of it happening:
That one sounds more like the “normal” caching issue I originally mentioned at the top.
Desmondev stated it never comes back upon save/reload, which I can’t reproduce.
I figured, but i just thought it was kinda funny that it happened to me on the same day were talking about this and on video…
Besides its always kinda cool to have actual video of stuff like this happening to showcase it 
…even tho it would be nicer if it didnt happen ofc
Tiled was doing this to me, then I went to spritefusion.com only to have the same issue. Odd. I can only imagine its an issue to do with the tile sizing, but…