Thanks R C-R. My difficulties, all seem to come from the install of El Cap'. whilst rearranging images and deleting some unwanted in Photos everything froze (never happened in iPhoto), left for 10mins. no change, no response anywhere. Power down disconnect all, leave 10 mins, reconnect and power up, its working again.
Go to Affinity. Try scroll down finder to Photos again. and instead of just not loading as before, it loads and I can access my album of 'Photos for Edit' No problem getting images for editing (Done this process 2 or 3 times now).
I have images taken using JPEG+RAW both seem to open ok in Affinity and I can edit-develop-tweak then export to Pictures as JPEG (don't seem to be able to export directly to Photos). Have to then move images into the Photos albums I want to use. Only concern at the moment is about originals being overwritten, I always click don't save altered image in the box after I close the file after export. Don't properly understand how all this works just want to use it. Really don't want to lose the originals, it seems ok at the moment. Guess keeping SD Cards is a good habit.
