Big thanks to the Valve team for their help in testing, and great communication about the process. There are a few minor features that don't work perfectly on Steam Deck at the moment, the biggest of which is the replay video export feature. Until this is resolved the replay video export feature is disabled on the Steam Deck. Fullscreen mode also was causing some problems, and is disabled at the moment, which shouldn't cause any issue as Fullscreen Windowed mode (the default) works great.