Hey, thanks for the comments!
1. I was pretty happy with that second mechanic. Thanks!
2. Good feedback, I'll think on ways to give that section more clarity.
3. It's really meant to be an opening for the GM to decide if the event was an accident or on purpose and allow the game to start with a complication and a little mystery. Otherwise it may be a trivial trip back to the past to make the right adjustment. If it wasn't an accident, then perhaps the group meets opposition from other time travelers, for example.
4. That bit assumes the players want to return home and is more of a "If you don't want to die, listen to my instructions" type of message. However, I can see how it may be appealing to simply stay in the past though and doesn't come off like that. Good catch. Great idea on what do do with the money. That could be part of character generation.
Thanks again!