DarkNick

Thanks a lot, Dan. Especially for the quick answers. It really did help. And also thanks for the suggestion of alternate converting.

I just uploaded the files. As far as I know this must be one working on stack in Affinity and the other one which causes the crash.

You're welcome. I didn't know that there are that big differences in HEIC files. As far as I know there are just some of these files which cause Affinity to crash. A private upload link would be nice, so I can send you a few files.

Hey @Dan C, thanks a lot for the quick answer and the brushes data. Now they are fixed. I just had to import them without deleting other brushes I bought. Unfortunately the disabling hardware acceleration didn't bring the results at all. When I disabled the paralell stacking, it worked a bit better, but it's still crashing. My GPU drivers were updated at both points when Affinity crashed. It seems, some of the HEIC-datas might be defective because some of them are only 700KB at data size. They were taken with an IPhone 11 Pro. But could this be? I mean, they have been able to transform into JPEG's but with Windows Photo Viever instead. Best regards, Nick

I recenty noticed that two of the standard installed texture brushes are not complete in preview. I can still draw with them, but the flow and the different variations are missing. That's really sad because I use them very often. I didn't change or modified them, so I don't know how to restore them. The broken brushes are no 03 and 04 in the texture folder. The other problem I have is at stack editing. I just wanted to convert some HEIC-pics into JPG and suddenly Affinity crashed. Even after reducing the numbers of pictures and turning off the paralell edit, it still crashed. I took some screenshots from the brush folder and my performance settings. Maybe they'll help you. Thanks for your advice. Nick