We just confirmed an incompatibility issue may happen if you run BIAS Amp as a Reaper plug-in on Windows 10. The symptom is that the user will not be able to run BIAS Amp even it's already configured in Reaper's plug-in management.
Please rename your BIAS Amp folder, as the following:
Change it from:
C:\Users\<username>\Documents\Bias
To:
C:\Users\<username>\Documents\BiasBak
Then please try launching BIAS Amp again in the standalone app as well as in REAPER. it should work after this re-configuration.