I've been playing around with my DVD authoring tool to try to see if I could make a DVDi boardgame. But I can't figure out how to do the timed events and where to store or access variables for scoring. Anyone got any ideas?

DVD players are very limited - they only have a handful of 16-bit registers which can hold data. You'll need an authoring tool that lets you control what goes in them, probably by writing code. I wouldn't expect to find cheap tools that will let you do that.

To do timed things you'll probably want to play a video of the appropriate length. If you reach the end of it time has run out.

Okay, so if I where to play around with an open source DVD authoring tool. Where would I possibly find information on how to access those registers?

Also, having played the DVD version of Atmosfear I can safely say that there must be a randomization function either on the dvd or the player and that you have to be able to keep a countdown going seperately from whatever is playing.

Though the seperate countdown might instead be an ability to play several layers of video at the same time. Which I base on the fact that the background behind the gatekeeper kind of looks like it loops seperately from him moving. (That could also be bad editing and pure chance the times I've played it)

So where might I find how to access the randomization on a dvd player OR alternatively how to program it to play things randomly?

Without knowing what tool you're using, I can only suggest looking at the documentation for it, or contacting their technical support.

There's some basic information on the details of how DVD navigation works at http://www.mpeg.org/MPEG/DVD/Book_B/Intfunc.html - they call the registers "General Parameters".