Premiere Pro PC timeline only plays for a few frames and then no Audio after installing Miraizon DNxHD / ProRes Codec
According to Miraizon support this is a peculiarity in Premiere Pro handling of ProRes that causes it to interact "very inefficiently" with the the codec. There is an update forthcoming but until then they suggested this as a work-around: 
Move the AppleProResDecoder.qtx from the /Quicktime/QTSystem/ folder to a temp folder.

I still get some inconsistencies with various files under these circumstances such as "Media Pending" messages that aren't resolved and spotty playback.
This is currently working for me: 
For editing:
Leave the AppleProResDecoder.qtx in /Quicktime/QTSystem/ and move the MProResCodec.qtx from the /Quicktime/QTComponents/ folder to a temp folder. Restart PPro.
When I'm ready to export my ProRes:
Then when I'm ready to export to ProRes, I move the MProResCodec.qtx back to the /Quicktime/QTComponents/ folder and move the AppleProResDecoder.qtx into the temp folder.
Restart PPro.