I just did the KMEM 36R RNAV approach and had the same behaviour as described above. P DES just flashes when you press PROFILE but never arms. It does capture the glide if you press PROFILE when the diamond is cantered.
I have the same issue on every flight - but I did notice the IRS aligns and the warning disappears once you press the ALIGN IRS button on the FMS INIT page.
I just had a total shutdown of all systems and engines of the plane in air and then a nosedive to the ground until I got an aircraft stress message. This happened a short few minutes after initiating the descend - flight plan: KRNO PVINE5.HALLE WNDEL HAWKZ7.LKV KSEA
I did notice there was zero fuel in the aircraft as it was falling out of the sky but not sure how that happened as I lifted 20,594lbs of fuel as per Simbrief.
I hear you and maybe it is, but the fall out of the sky I experienced and that I saw videos of other people reporting, nothing ever shuts down in the aircraft, it literally just drops out of the sky with all systems working.
I have noticed FSUIPC being mentioned a few times with this issue. Is there anything we can do from our end to mitigate this while we wait for the patch?