I'm not sure if this is a bug. I was trying to write some simple tests to learn more about the limits of our DOS.
Simplest attempt:
This will save the current program as "HELLO", but the program is terminated after the save. The message never gets printed but AFAICT, it should. Tried it on a C64 in case this is a limitation everybody but me knows about, but it worked as expected.
R42, default settings (i.e. host fs, did not try any other type of fs)