@airnorth
Perhaps worth checking you have the CDI source switch set to RNAV, and the KNS-80 is in RNV/ENR or RNV/APR modes. VOR or VOR/PAR modes will not appear to be correct RNAV readings, as they render the unit equivalent to a NAV3 radio by providing course deviation information relative to the physical VOR station.
Hope this helps! If not, perhaps if you can send us a video or some screenshots by raising a ticket https://support.justflight.com/support/tickets/new and we'll pass them onto the developer to look at?