Is it too late to suggest just getting a dedicated Blu-Ray player?
As much as I love HTPCs, the current crop of Blu-Ray software is absolutely dreadful and not worth the trouble. You'll fight with it to get it updated for new keys practically every time you use it.
Couldn't you just lossless remux/strip the main audio and video stream into an .mkv container and use MPC-HC? Who needs blu-ray software? And if you install something from dvdfab that strips the DRM so you can MPC-HC to play the main .mt2s file anyway.