OK, current theory is that it's depending a version of the System.ComponentModel DLL that isn't in Windows 7 (and I'm not sure about 8).
I'm guessing that if you've not updated to 10 yet you won't do it just for the sake of my silly little card editor
so I'll see if I can rebuild it without that dependency. If you like, you can blame Microsoft for taking installer projects out of Visual Studio - I'd rather have made a proper installer instead of just a ZIP! Bear with me and I'll try to work something out.