I know there is a way to custom make your own, but that requires coding.
What type of coding? does the app contain it's own scripting language or something?
I would like to see cards be less verbose. Like the Uneven Ground card reading something along the lines of "Rough uneven terrain, movement hampered." That is a personal thing, I like writing that is quick and gets to the point using as few words as possible. It is also a trick I was taught during my graduate work, to get the most information across as quick a possible, it helps people retain information better.
I can recommend Paint.net for layers, it is free software. I do not know if it opens .PSD files, my other PC has crashed so i can't test that.
I have not played MKD for so long, I have no one to play with these days. I don't know the rules, figures, or game mechanics like you guys do, but I would like to get involved in this project in some way!