Comcast DC50xu DTA doesnt work with WMC and IR blaster.

Comcast's required DTA box doesn't wanna work with my bedroom PC and it's IR blaster. I tried following the instructions on another site but I run into two problems. The first is that when WMC scans for signals it doesn't recognize it as a set top box. I can fix that by doing it manually but I'd like the two be more familiar with each other. Second, when I start to program the IR blaster with the dta remote, WMC tells me it knows the codes from the first couple of presses but the blaster isn't able to change the channels during testing. I'm stumped. If I can get this working ill be in bliss.

Anyone have any experience with this dta box or WMC and IR blasters in general?