I am studying for my GPEN also. I will look at the material i need to know and tell you which laws to be aware of.

I think C++ a good start to learn a compiler lang.. i would go into Python, C and Java after... maybe Ruby if you want to write Metasploit plugins.

I actually applied a month ago... no response.. it seems from his recent post he is going through tough times and it seems they keep the volunteer base close knit.

I will second that go for the GCIA or CCNA its good to have a good understanding of base technologies such as TCP/IP and FW configuration.