In windows I can hold control and use my arrow keys. When I find a file I want to be included in the group selection I hit the space bar(I think this is how it works) and it will add to the selected list of items.
I'm not working by file name, I'm working by picture preview. So the ability to scroll through the list and see previews is important while group selecting. I'm trying to delete pictures. I have thousands in one folder. Should I use win32 to do this? or am I just missing how to do it with OSX?