In character studio, you can import both rotation and position type motion capture files.
Biovision (.bvh) files contain limb and joint rotation data.
character studio marker files (.csm) contain raw marker position data generated by a motion capture device: markers are attached to an actor during a motion capture performance.
Marker files typically require some calibration. If necessary the biped is sized to fit the markers first, then the biped limbs are oriented to align them to the markers. Marker files should be loaded with keys at every frame and no footstep extraction, this is required for calibration, and this also enables the calibration controls. Calibration controls are the second row of buttons on the Motion Capture rollout.
The .csm marker file format now supports a prop bone in either or both hands. See Prop Bone.
Key reduction, track selection, footstep extraction, and clip looping are some of the options available using the Motion Capture import filter. Key reduction makes it easy to manipulate the biped and personalize the imported motion capture data. Extracting footsteps from motion capture data prevents inappropriate sliding feet, a common problem with motion capture data.
Typically you do not use an entire motion capture clip as is, unless you capture motions at a studio for your own production. You should become familiar with the body motion in the files you have, then use Motion Flow mode to cut portions of these files together to create animation. For example, take a stretch motion in one clip, and combine it with the walking motion in another clip. The edited script can then be saved as a .bip file using the Save Segment command on the General rollout. Load this .bip for standard motion editing. This provides a good starting place for you to edit the result to your liking.
All motion capture controls are on the Motion Capture rollout.