this didn't happen with previous versions
I saw this happen on another project with 4.3.0 yesterday, there might be another message in the log saying that a script doesn’t fit into a memory bank. The error isn’t very good but it’s saying that one of your scripts is too long and needs to be reduced in size or split into smaller parts. (Dialogue events now take up slightly more memory to fix a bug that was found)
Check out the second half of this message on GitHub where I see the same issue and gave a fix https://github.com/chrismaltby/gb-studio/issues/2098#issuecomment-4693926923
I’m going to work on improving that error message for the next version.
If you want to look at your project directly you can submit an issue at https://github.com/chrismaltby/gb-studio/issues to share your project files.
You should also be able to still open the project in 4.2 if you want to keep using the older version