Definitely, I hate giving up things! I can't miss this challenge, it's so cool! So i'll try to manage better my free time, and work on this.
I made some quick initial sketches. As I'm not sure how I can proceed making things that tranform in others, I'll focus in what is more clear to me now, the robot. What I have in mind is some sort of japanese style mech, instead of autobots.

https://img55.imageshack.us/img55/6915/sketch072aa.jpg

https://img466.imageshack.us/img466/858/sketch060xx.jpg

I made this sketches for the vehicle, but I'm not happy about them. I believe vehicle will be more defined when I get a reasonable shape for the robot.

https://img148.imageshack.us/img148/598/sketch058gt.jpg

https://img148.imageshack.us/img148/9271/sketch044rs.jpg