I haven't heard of those specific problems before. When there are multiple random problems like that then it is best to reboot the watch before using it again. If that doesn't help then please send the wkt file for that workout to info@workoutdoors.net and I will take a look. To do this tap the Export button 3 times quickly.I've had a couple of watch app crashes, I think they have all been on the connecting sensors screen just before starting a workout. I am using a Stryd and a Polar HRM, as well as using my AirPods to listen to a podcast via Overcast on my watch.
I've also had 2 workouts fail to record properly. The most recent was this morning, essentially at a certain point the time elapsed stops getting recorded properly, resulting in an almost infinite pace, at some point later it starts again. The same period of infinite speed has no heart rate and no power data, the elevation and GPS logs are fine.
My guess is that there is an issue getting data from the HRM and the Stryd and the app is getting confused by this especially as I think pace is derived from the Stryd.
When the workout is uploaded to Strava as a FIT file the total time elapsed is short by the amount of infinite speed resulting in some really wonky stats.
Luckily I was able to use HealthFit to export a FIT file based on the Apple Fitness version of the workout which has uploaded with the correct pace data (even if it is missing a section of heart rate and power data).
Would you like me to send you the FIT files? IIRC there is some debug data for the workout I can export too?
To be honest I probably won't spend too much time investigating because no-one else has mentioned it and the app hasn't changed since last year. However it could be related to recent versions of watchOS, Stryd etc, so if more people start reporting it then I will look into it in more detail.