Please attach the logs. It would be great as well if you can update to INDI/KStars nightly before testing this again. To use the latest release, click on "Mate Terminal" and then type the following:
Thanks there is new QHYSDK with an updated INDI QHY driver (v2.1). It should be available in the repos later tonight. Please test again and attach the logs.
Jasem, thank you so very much for keeping on asking QHY for fixes. I can confirm that with this SDK and driver the filter wheel started working again on Linux.