I'm using latest OSX and trying to preview native image from Pentax K-5II, connected to (updated today) StellarMate via GPhoto2. It did NOT crash if I used fits format.
I have now reverted to Kstars 2.9.3 and things are back to normal. No crash on preview of native image.
EDIT: Checked StellarMate and it's Kstars is at 2.9.4
Yes, there was an auto crash report sent to apple - about half a dozen actually. Not sure if you are auto-notified or if you need to retrieve it. If I knew where to look I could send it to you directly.
I just did some testing and I can confirm that you are correct, the version of libraw that got bundled into the app for some reason caused kstars to crash. there were two versions of libraw on my build computer and the "wrong" one got bundled up. I will try a fresh build and see if it bundles the correct version.