I may continually post here as I encounter more bugs. Here is just one: mj_set_mocap is buggy. Whenever I only change the pos field obtained from mj_get_mocap and update the simulation with mj_set_mocap, the the mocap body moves to the desired coordinates, but the quat field changes unpredictably. Similarly, whenever I manually define the quat field, update, and then gather mocap data again with mj_get_mocap, the quat field does not have the values I had just defined. This results in unusable control of mocap bodies using the API. Could this be caused by my not having motion capture activated in Mujoco? I caught this at my workstation without the Optitrack connected.