Hi,
I'm having some problems in REAPER with Session Guitarist Electric Sunburst (Deluxe). During playback, mouse operation of the GUI elements is getting interrupted, making it impossible to tweak the settings. When playback is stopped, everything works normal. Same behavior on Electric Mint. I'm also owning Prime Bass and Strummed Acoustic where everything is OK during playback. So, I'm guessing this is not a REAPER thing. Hopefully someone can chime in and test on his/her system. I'm working on Win10 x64, latest REAPER 7 and KONTAKT 7 versions.
Here's a link to my question on the REAPER forum:
https://forum.cockos.com/showthread.php?t=294255