We released a patch that fixes the issue where, during the Prologue, the application would crash when Okabe played a video on his cell phone.
If the issue persists, or you experience other issues, please let us know on the Technical Support Forum.
We know that many of you were looking forward to this title and we apologize if you encountered this issue. We want to bring you the best possible gameplay experience. Thank you for supporting STEINS;GATE and the Science Adventure Series!
Sincerely, -Spike Chunsoft CS Team