I tried your repro case, and it behaves the same way in 1.9.3.
Did you experience a regression between versions?
The way the cache size is calculated, is a “good guess”. As the font has “all characters” set, we don’t want to create a possibly gigantic texture.
So the solution is the recommended one, if you know you need more cache space, you set the cache size explicitly.
So for now, unless you can find a regression, I will mark this as “works as intended”.
Thanks for the test file!
What is the license of the file, would it be possible for us to add it to our unit tests?
No, worry It is cc0. But I can probably provide the smaller model for the unit test if it makes sense =)
Edited: I added the just cube model with 2 root bones
simple_model_with_2_roots.zip (1.0 KB)
I did not notice such a problem in my working project on 1.9.3. Although I have run and tested it many times during the development process
Perhaps it was just now that some text actually changed, and you hit the cache limit?
The release has now been updated with a fix for the model crash. Please update the editor again!
Thank you! It works!
Yes the text changes all the time in one gui when moving between levels
I have updated to 1.9.4 and I get this warning in the console:
WARNING:GAMESYS: Material /builtins/materials/tile_map.materialc has specified a vertex constant named 'world', but it does not exist or isn't used in any of the shaders.
I see the following constants indeed in the built-ins material:
This is a warning, but it has been resolved for the next version of Defold:
Ah great, I couldn’t find it on the forum but forgot to check the repository indeed 
@d954mas We’ve now pushed a fix for your reported issue (Changing font resource for gui broken in 1.9.4 · Issue #9653 · defold/defold · GitHub)