I just rooted my NC last night (CM7) and have been playing with it ever since. But I can't download Angry Birds from the Google Market

When I search for "angry birds" it comes up and says it is free on the search screen (as opposed to downloaded like other apps I have gotten), but when I pick angry birds there is no download button. I can't figure it out?
I though maybe it was somehow able to see I had Angry Birds from the BN Nook market (from before I rooted), but I also had Olive Tree's Bible Reader and had no problem downloading that. I was able to download Angry Birds Rio, so it won't be the end of the world or anything if I can't get the regular one--but gosh darn it, I want that one also! Anyone have any ideas?
Mary