MacGB

Update:
This works great, thanks Walt ! (But you already knew that of course 😃)! 
Ben 

Thanks Walt for this suggestion.
I will give that a try, 
 Cheers
 Ben

@EmTThanks for the info, glad to know it's not me 😉. Hoop it wil be solved soon.

@Pattebear,
A couple of suggestions (you might already have thought off)
1. Did you (and others with this problem) try to start-up in Safe-mode" and restart afterwards. ?
2. Did you try working with Affinity without an internet connection (If Grinning Shark is correct, this might help)
3. Is it possible to install the version from Affinity website, because that runs smoothly (almost ). I suppose you have to contact support before you do this.
HtH
Ben
 

@Pattebear,
A couple of suggestions (you might already have thought off)
1. Did you (and others with this problem) try to start-up in Safe-mode" and restart afterwards. ?
2. Did you try working with Affinity without an internet connection (If Grinning Shark is correct, this might help)
3. Is it possible to install the version from Affinity website, because that runs smoothly (almost ). I suppose you have to contact support before you do this.
HtH
Ben
 

Hello RHMB,
I did already post (the wrong way I guess) a few hours ago, Hence this new attempt:
The "Edith with Affinity Develop" stopped working "ages" ago. (If I remember correctly, with the introduction of version 1.7). I disabled this one a time ago , also because it's limitations add nothing special to what Photo's can do in the meantime. Lots more possibilities for that matter. Of course I tried with this new version, but it simply doesn't work for RAW, as you noticed.
Glad the extension "edit in Affinity" does work for you as well. I find this one much more valuable if I want to use layer or other advanced functionality. However using this option has, to me,  one big disadvantage. If you save back your RAW-edits to Photo's, and like to continue afterwards were you left it isn't possible. When you re-open the file from Photo's, Affinity will start again wit the original RAW, without any edits. So you have to start over again, the history is gone ! Other apps like RawPower, and f.e.On1 keep the history, so you can pick-up where you left. Due to the way apps and Apple Photo's work this is limited anyway.
If you like there is a very interesting article by Nik Bhatt
https://tidbits.com/2019/06/14/the-ins-and-outs-of-non-destructive-editing-in-photos-for-mac-and-ios/
Ben

Well on the positive side:
It works for RAW, which it didn’t, the extension develop works for jpeg. That’s an improvement also.
It’s still a beta release for which Affinity indicates they are still working on a solution because it hasn’t been fixed in this beta.
so I keep my hopes up.

@ henryb,
Did I misspell or don’t I understand what you are writing (English is not my native language) ? Because that is what I wrote in my replay to Brantc.

I am able to use the extension "edit in Affinity Photo", I can make changes, they are saved back into Photos. However when I reopen with "edit in Affinity" to continue editing, It opens up the original RAW file without the previous edits. So the history isn't saved. (I did not make any changes with Apple Photos or any other extension on the same picture). In the Beta it still has the same bug.
I reported this behaviour already in the Beta's. I was assured that it would be solved as from the first release of the official 1.7. Still no change. Very disappointed and quite useless in this way (for my workflow that is). I am running Mojave 10.4.6 and Affinity 1.7.3
 

Hello Chris B,
Thanks for the info
Some extra info. When I use a jpeg-file, it works fine.Because off that I was thinking it might have something to do with "not-flattening" the image before writing back ?
The needed flattening is perfectly handled now with the Affinity extension "Edith in Affinity Photo" in the beta, This is really a joy to work with. 

In  Apple Photo's Opening up Affinity Develop with the extension "develop" fires-up a Develop module in 1.7. with the RAW-photo from within Apple Photo's. However saving back (with or without adjustments) reports an error saying "Edits with Affinity Develop not possible, an unexpected error has occurred" (see screenshot though that is in Dutch, hence my translation  )
The file in question is a RAW file from my Panasonic G80 extension .RW2.
 When I use the extension "edit in Affinity" it works ok.

Hey Chris,
Thanks for sorting that out. That did the trick,
Noticed also that with the "edit with", it opens a tiff and not a RAW.
One tiny problem now (but don't bother) if I try to use the "edit in" extension from Affinity Photo 1.6.11 it opens up Affinity 1.7 beta, no way that I can get 1.6.11 to pen with this command.
Tried deselecting all extensions and rebooting my system to no avail. But then again it's no problem; glad that you figured this out and that the "open in" extension is working properly in 1.7