Been suffering similar frequent crash issues since updating to 3.0.1. Sometimes it just seems to happen at random times, not even related to user interaction but when trying to use the removal feature, it happens a lot, and seems to be triggered when trying to make the removal selection.
Please try to recreate this crash then open Topaz Photo AI, go to Help > Open Log Folder, then please send me all of the files within that folder. You should be able to attach them directly as a response to this thread.
If you would prefer you can securely submit your files(s) to my Dropbox using the link above in this thread. Make sure to send me a note to let me know you sent something.
I have updated the program again hoping it would fix it, but unfortunately it has not. I have uploaded the log folder and crashpad folder to your dropbox