I'm sure some of you already know this but since I had been struggling with it for six months before I finally figured it out I thought I'd post this to help some of the new folks who use Affinity Photo as their external editor.

I am not a PhotoShop guy and as great a tool that it is, Adobe subscription model just doesn't sit right with me so I went with Affinity Photo (AP) as the external editor for CTA/CA. (Note: I'm on CA4 Pipeline; previously CTA3 Pipeline). For the longest time it was a constant hassle because whenever I'd launch AP from CA/CTA it would work great but then I had to export it as PSD and then go back to CTA/CA and re-load the character from that saved PSD file. Not fun at all, if you have to do it every time you edit your character. Made me envy PS users who were enjoying full integration of CTA/CA with Photoshop (and I imagined they were probably laughing at us, non PS users, too :-)).

Until I eventually got tired of it and stumbled across a very simple solution. Here it is. (I assume that you already have AP set up as your external editor).
1. Open your Affinity Photo and go to Preferences.
2. Go to General tab and check "Enable Save over imported PSD files" option. (see screenshot)

Then suddenly everything magically fell into place! CA would launch AP. And after making some edits all I need to do is to hit Save and your character in CA composer gets updated automatically! It truly feels like magic, I tell ya. You'll appreciate it even more if you had struggled with it like I did.

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