Hello,
I have been finally able to test this new plugin DLL with USBCAN2 device and it works well on my side. Can you make sure you have copied the DLL to the right place and that you do not have multiple FreeMASTER versions.
In case you have multiple FreeMASTER versions installed, I recommend to re-install the 3.0.2 version and copy the attached DLL to installation folder that was used for this last installation.
The properties of the DLL should show version 1.8.0.0

Regards,
Michal