[BlkCat]

Don't take my word for it, because I'm new to flashing too, however I'm 99% sure that the only time in which you are required to flash a stock/official release is when you're upgrading your radio.

Example:

You want to flash to the "Almost OEM Windows Mobile 6.1" release, you currently have a radio lower than 3.xx. So what you would do is, first you would flash to the Sprint Leaked ROM to get the radio, since the custom ROM does NOT contain the radio. Then you would flash to the Almost OEM.


So basically, I think you only have to flash a stock rom when updating the radio.


Edit: Warning however, if you DO flash a custom ROM for a higher radio without first upgrading your radio, you can, and most likely will brick your phone.


Good luck!