Once the application was installed and started, press the Options icon and you can see the storage path of recordings. I've checked the available controls from within the program and it appears that you can't play back those files, instead a media player is needed instead.
Download and install VLC Media Player and use File > Open then browse to the recordings path and you should have the possibility to play them. Please notice that you won't have the possibility to use fast forward on a file that's currently in recording mode.
Same thing applies to the mobile versions as well. Transfer the files to PC to play them. It's easier and more convenient.