Hi Daniel,
sorry to read this! I don’t know why Franz is crashing like this. Could you paste the full crash report here?
Internally, MIDI Translator Pro uses the open command to execute the given application, e.g.
open '/Applications/Franz.app'
You could try if it’s crashing when launched with the above command from a Terminal window.
In general, though, I think that the creators of Franz would be best suited to fix this issue.
Let us know what you find out. Thanks!