Dreambox / Sky / MythTV

I've looked for information everywhere for the past few days on this

As I understand it, correct me if I'm wrong:

1. In relation to DVB-S capture cards on PCs, NDS can be overcome using a CAM integrated into the capture card (is there anywhere I can get really detailed information about CAMs/CI etc?) or (only closed sources, or so I've heard) windows-only emulators.

I have also read that people involved with the MythTV project are reluctant to use emulators to crack NDS in their software, even if the source was available.

I also hear that the Dreambox can be flashed with linux-based firmware that includes NDS emulators etc, although I also read something about card sharing in relation to this so maybe it isn't an emulator. I'm assuming since Linux is open source that the code for these emulators is available. Therefore could it theoretically be adapted/ported for use in MythTV? if not by developers then by somebody else.

I also hear that NDS can be easily changed by Sky to do with re-issuing of cards etc.

Any answers on these issues would be very helpful.