I think I figured out why my video card isn't in the HW acceleration list - while it does support DirectX 12, it doesn't support feature level 12 which is required (according to the Affinity Photo Windows requirements page). Interestingly enough, the built in video adapter on the MB does because that is in the HW acceleration list. While dxdiag doesn't display its capabilities GPU-Z does and it shows that the built in GPU supports DirectX V12, level 12_1.
Thanks again for the help.
josec41 got a reaction from walt.farrell in Random Crashes in Photo