Steps to recreate:
[LIST=1]
[*]Replay->Load Replay
[*]Click 'OK' in Replay msgbox
[*]Select a .zplay file and click 'OK' in the Load Replay (.zplay) window
[*]Player window freezes for several seconds
[/LIST]
There should be some kind of feedback that the player is trying to load the replay and it hasn't just frozen.