yeah, I wish too I could flash whatever rom I wanted... it can be done for sure, but I think that it is disabled in koyoteflash to discourage piracy or whatever...
ofcourse you can use the kickflash as a clockport adapter, we even have the original clockport schematics in the a.org images... :-D
better get a 3.1rom too, then install os3.9 and don't a single reboot to start 3.9 (except the power-on, lol) plus you can have the usb stack available at boot time...