Normal
Not a direct answer to your question as I am not aware of any means of switching between internal and external players once the config. has been done, however... You may want to take a look at the pre-release 1.15 version which has the option of a different player (internal or external) for Bluray and DVDs, i.e. you should be able to set up PowerDVD just for Bluray and the internal player for DVDs and saved videos which will refine things a little better. Also currently under developement and testing is the intergration of the madvr renderer which in conjunction with the latest LAV filters will playback 3D .mkv rips in 3D on the MP internal player. So in future there maybe some additional options for 3D playback without having to use an external player at all.