UI Panel
Source armature [Set source armature], select your source armature object and press this. Below the source button is skeleton model. This selects one of source skeleton map files.
Target armature [Set target armature], select your character armature and press this and object name appears to the left. Below the target button is skeleton model. This selects one of target skeleton map files.
This create proxies between source and target armature object. After poressing this, your caracter should jump to the source bvh-armature.
If some of the bones are not locked, something not match sourcemap or targetmap. The bone names are important role. Just Select another map and try again.
Then one or more bones may get wrong orientation or axis. Now they can correct with tweakers.
There are few sliders. Basically they are shortcuts to target armature constraints influence. But these few is very common to tweak.
Pelvis location influence: Some cases you may not use bvh locations, just raw joints movement and you make character movements another way in the scene. That case set influence to zero.
Shoulders rotation influence: Some cases shoulders rotated too hard in bvh. They can softening in here. Neck rotation influence:
Some cases neck rotated too hard in bvh.
Skipping frames On default (1) every frames will be baken to action. Set this to (5), every fifts frame will be baken. Overwrite existing action If not selected a new action will created, and if selected bake will happening to the existing action.