Blaster's Mystery Ports...

I just recently got leader class Blaster, and noticed a few ports he has, some of which I can't figure out any purpose for...
I get the headphone jack, and USB ports, but what is that other one on the other side? It kinda looks like the power cord port on the back of a playstation, but squished down a bit. It's the one next to the 'power button' on what turns into his right leg.
Also, what's with the peg and ramp-attachy-bits on his butt? I get that the ramp-attachy-bits are for attaching ramps, but it just seems kinda odd for ramps to just dead end like that into a wall. And for two ramps to attach in the same place with only about a centimeter height difference... And I have NO idea what that lone peg is for...
And then there's the square hole on his front... It's too small to fit a 5mm peg, and it's too deep to seem like something decorative...
Any idea what these are for?
I get the headphone jack, and USB ports, but what is that other one on the other side? It kinda looks like the power cord port on the back of a playstation, but squished down a bit. It's the one next to the 'power button' on what turns into his right leg.
Also, what's with the peg and ramp-attachy-bits on his butt? I get that the ramp-attachy-bits are for attaching ramps, but it just seems kinda odd for ramps to just dead end like that into a wall. And for two ramps to attach in the same place with only about a centimeter height difference... And I have NO idea what that lone peg is for...
And then there's the square hole on his front... It's too small to fit a 5mm peg, and it's too deep to seem like something decorative...
Any idea what these are for?