I am using the most recent beta version (I don't recall the version number now), and I have very erratic and sluggish performance all around. The app takes ages to start up and load the opening screen, and movies take ages to load.
In addition to that, some movies only load half way, i.e., when I click to select that movie, the screen loads the profile, but nothing else, not even a button to start the movie. This consistently happens for the same movies, i.e., I can never load that specific movie. It happens to new movies (e.g., a recent New Zealand one that is yet published in the production version) as well as some older ones.
Also today a movie got stuck after 6.3 km, there was nothing else to do than kill the app in the task manager. On re-entering the app, the crashed ride uploaded, but I was unable to re-start it from the recent rides menu. I tried 3 times, and the app crashed to desktop all 3 times.
This is on an old laptop, on which the production version is also installed. That production version performs in an acceptable way.