You were right, I had copied over the existing folders. Started with a fresh appdata with only my profile folder in it, but still having issues with mappings. Created a new profile and set it to use the 360 output driver and assigned it to my 2nd gen controller using BT. Using Xinput test the right joystick moves the left stick on the screen and nothing else works. I'll give it another go when you push out a new build.
edit: I did try and run it with the scp bus disabled in the device manager, same results.
Asus STRIX X299-E GAMING MB, i7-7820X 3.6/4.5GHz 8-Core, 32GB Corsair Dominator Platinum (CMD16GX4M2B2400C10), NVIDIA TITAN X (Pascal), Samsung 970 Pro 1TB M.2-NVMe w/Western Digital 2TB (WD2000F9YZ), Samsung 65Q9FN QLED, HTC Vive, 850w PS, W10
I just grabbed InputMapper 1.7 (Nightly Build) 1.7.6612.19795 to try out and noticed theres no Plugins folder in the archive just a Release folder. Was there a change? Or did you just maybe forget to add the Plugins folder lol