The project died a while ago. I believe the owners own prototype 2 if someone can correct me if I am wrong?
https://hackforums.net/showthread.php?tid=4978432
I own prototype two. On it own it works ok but they have never developed the free plugins they said they would since I have had it.... Nearly a year!
It's coded in C++ which not so common these days which is cool but the licensing system has had its troubles. I dornt use it tbh but when I do take it for a whirl I just wish they had developed it more. They might hook you up a license if you were lifetime of legacy link but I doubt it. Worth a try?!