This seems to be happening pretty consistently. I was building a character; more accurately I was modifying Martha character by replacing a few sprites and adding a few new ones. I did a few PSD (Affinity) round trips as I was doing some tweaks along the way and everything seemed to be working fine (well, relatively fine) but at some point when clicking on Edit in External Editor option I suddenly encountered this message (attached).

I understand what the message says; I am aware that G2 components are vector based but converting vector to pixels is something that CTA/CA have been doing for a long time. I used to do it all the time in CTA3.

So I clicked OK. After that nothing happened. Meaning the template wouldn't open in Affinity Photo like it normally does. After a few trials and errors I discovered that this only happens after a G2 facial component (eyes or mouth) has been added to the character. Everything continues to work perfectly well in the composer and in the project but in essence I lose the ability to modify it in PSD editor anymore after that. I do not recall seeing anywhere anything about G2 facial components being not compatible with G360 so I would have to assume that it is a bug.

Now it is possible that everything could be working peachy fine in Photoshop, but again, I used G2 eyes and mouths in my G3 characters all the time in CTA3 without a problem.