Actually, I can see from our installation records, that a few Win7 users did actually manage to install and run Animation Paper. So at least for some it does work.
I have now dug up three old releases we’ve made. Maybe there’s a change one of them will work for you. Worth a try at least.
Here’s Alpha 1, Alpha 3 and Alpha 5…
https://www.dropbox.com/s/a0txhtiwegwyo19/AnimationPaper-Alpha1_x64.msi?dl=0
https://www.dropbox.com/s/4dp34or7qlw20pm/AnimationPaper-Alpha3_x64.exe?dl=0
https://www.dropbox.com/s/irenqfien91oage/AnimationPaper-Alpha5_x64.exe?dl=0
Fingers crossed!