Honestly It sounds weird that its not working. it looks like everyone else is able to get theres to work just fine (as like 75% of ppcgeeks is sprint) so I wouldnt see the problem.
Would try removing and readding the app naturally and if no go then possibly another app could be interfering with it which I wouldnt know what would interfere with it.
Also there are other 6.5 cabs out there (I think when I saw last there are 3) IF I find the links ill update them for you so we can choose the one that works.
Edit***
http://forum.xda-developers.com/show...&postcount=549
This is the one I used for my Verizon TP2
http://forum.ppcgeeks.com/showthread.php?t=88683
Not sure if its the same but I didnt need a Reg fix so I think its different.
Also Check post 9 for Skymarket.cab. This would be the third one (names different and again no reg fix)