I have my pictures and videos in google photos. I have even tried using takeout. But, when I try to find them on my computer I open them. A screen comes up to open or save the picture. When I press open or save, nothing happens. It flashes for a second and the same screen comes up over and over and over.They shouldn't need importing. You would just need to download the videos and photos to your computer and place them in a folder that the software can access.
Now if any conversion is needed (which I don't see why but you never know) then you would need to find out what the program requires.
This is all assuming you have the files in a google account and can access it from your computer.