VRChat doesn't receive data from VRCFaceTracking
VRCFaceTracking receives data (screenshot), but VRChat doesn't receive anything - OSC debug console is empty.
Different program (VSeeFace) does reach VRChat (but they use different parameters so no existing avatar with face tracking works)

I might need a little more context about how you are using VRCFT: Are you using an avatar that is setup for VRCFaceTracking? OSC data will only be sent once an avatar that supports VRCFT is loaded.
I repeated it today with a different avatar to make sure. I was in VRC in the avatar that (from description and another person's claims) supports face tracking, with OSC turned on when I started the VRCFT. The tracking is activated on the avatar. I used the latest release (v5.0.0-pre-2) from VRCFT with included custom libs (the one from here wouldn't initialize for some reason)