Roeney,
I take it you are talking about FaceTrackNoIR. I have it working with 1.2.7 but more by omission than by design. I forgot all about it and when first starting up DCS with 1.2.7 I started FaceTrackNoIR as I usually did with 1.2.6 and hey presto! it just worked. So my advice would be .... do nothing lol, or in your case delete headtracker.dll from 1.2.7, hope this helps.
breid