Hi have tested Publisher for regular work, and overall the app seems a little bit unstable compared to the retail version and is crashing a lot in the Print dialog where i usually do a lot of N-up work. I've collected a log which i think it will help you.
Edit: There was a recipe to make it crash everytime, at least for me.
New document with some pages. Picture frame in the master, Add pdf pages to the document, then go to print, put some N-up (2 per sheet in my case) Add cut marks then use the pdf Dialog box to save the output and voilá, crash but at least it seems to export the file.
I've used the exact same steps with the exact same pdf file in the retail version and everything is Ok.
Affinity Publisher 2 Beta-2023-02-17-111017.ips