Specifically used for a playable demo or trial version of a video game. Often interchangeable with 体験版, but 試遊版 emphasizes the act of trying out the game.
See also: 体験版
I played the demo version of the new game at the game show.
I plan to download the trial version and buy the full version if I like it.
Compound of 試 (し, 'trial') + 遊 (ゆう, 'play') + 版 (ばん, 'version'). The term is a modern coinage for video game demos.