Zeta+2 used to hang for me too. The sandbox option added in 2018.06 fixed it for me.
Prior to that time, I would
- cancel the scan
- move the plug-in out of the scan path
- run the reset
- put the plug-in back into the scan path
The DAW picked up the plug-in on the next scan (I use automatic background scan but manual scan or scan on start up should work too).