I have the same problem, and I'm based in the UK.
I spoke to Slingmedia , and we went online via a browser on my laptop, and still could not see the app available.
I have updated all the system updates as they have come out. i'm on android 2.2 as well.
I have asked sling if they could send the app to my phone, but you have to use the Market. Why? surely, they must have the code?
I'm quite happy to pay as well , no idea how to proceed, if you fix it be good to know how!
rod at rmlconsultants dot co dot uk
Spoke to T-mobile UK, numpty had no idea , and said that it is related to HTC and Android, but from what i've read i think t-mobile need to say it's ok to use on their phones.
Drop me an email and perhaps if you call me , we can conference a call into T-mobile so they know it's not an isolated case.