To install any of this software in this pack you must first install MRX_Sprint.cab to provision your device to be authenticated by the sprint servers.
--> i'm guessing this is regardless of who's ROM or whether one has "installed any of your earlier provisioning cabs" right?
This error: error "Cant get the deviceID from HTC_get_DeviceId()" when booting the phone. ...--> the sprint stuff is not getting your device id for the PRL updater that will run automatically the first time.
"the first time": As soon as you reboot after installing the Mr. x cab?
has sprint profile update auto booted for you yet?
When is it supposed to do this "automatically"? So, I install Mrx_cab & it'll reboot, then I wait & it should then provision & reboot by itself again? Or, do I have to run it again?
"On Juicy R2; I did not need to perform a hard reset or run the MRX_Sprint.cab.
I just installed the Sprint TV cab (Sprint TV_1_7_189014_0.cab) provided by Juggalo_X and its working perfectly."
It's a WVGA cab, probably won't work on vga (TP) but I'll try.
dev id error shouldnt be an issue unless its not overwriting CDMADEFAULT.txt and AAAInfo.txt in rom:
So, that's what mrx cab does? updates with dev id etc..?
my files:
cdma txt file has: "31000", what should it have to make this work?
AAAInfo.txt: none to be found. can you tell me what should be in it?
Sorry about all the detailed questions, I'm trying to figure this out for all us poor slobs that can't afford a TP2 yet! 
... but first i have to know how it makes the tp2 work...
Thanks in advance for any help on this one.
Most importantly:
2) install MRX_Sprint.cab"
? How does one stop provisioning on the ROM? Reboot right after setting up screen by pressing the x's? If so, exactly when & how would I get the ROM I'm on to finish provisioning after running the Mrx cab, "which is a provisioning cab".