Starcraft VS Level design

So unless you have been living under a rock you will know that Starcraft 2 was released today. :P
As a result I failed my will save to work on my level and just had to play some starcraft seeing as Ive been waiting for it to come out since forever :P

I still did manage to get a the basic bsp blockout of my level done in a few hrs.
However I did run into an issue in regards to the tunnel leading behind the waterfall.
As it currently is the tunnel is to high allowing the player to see top of tunnel when standing outside.
However if I make it to low it makes for a very long set of chairs.

My plan is to spend the rest of the night in starcraft 2 and get it out of my system a bit before starting fresh tommorow.