The leaking into the crankcase can be numerous things depending on how the valves are currently open/closed, what condition the valve seals & pison rings are in. Someone recommended moving the timing belt manually to a certain spot so that all the intake valves were in configuration to stop such leaks. I'll try and find the post and get back to you on that.
On a positive note, you are heading in the right direction with the huge leak on the IM gasket. Once you get rid of the large leaks, you can hunt down the smaller ones when it actually holds pressure.
*edit* Start here.
Boost leaks in Odd Places