I don't understand this point, why do you still need MPExtended?This can work using MPExtended and the MPExtended provider for MP2-Client.
See http://wiki.team-mediaportal.com/2_MEDIAPORTAL_2/9_Reference/TV_support for more details.
In the news section you said:
The cutting edge technologies of MediaPortal 2 now makes use of the matured and stable TV Engine 3 of MediaPortal 1. This makes MP2 a complete solution for daily use, no longer depending on additional TV components installed!