Visualize the external force in the local frame

[Yujin Kwon]

Hello everyone,

I have a .mot file with GRF data and external force applied to calc_r during walking.
Since the force is applied on a point in the local frame (i.e., calc_r), data in the point columns are always same throughout the trial.
When I tried to 'Associate Motion Data' for the loaded IK data and then right click on the loaded .mot file to 'Edit Motion Objects', I see the window as attached below.
Here, I assume I may need to change the value of 'Point Expressed in' from ground to calc_r to visualize the force on the frame where it should be, but when I do so, the animation stops playing.
Changing the answer for 'Apply to' from ground to any others doesn't make any changes in the animation either.

Does anyone know how to visualize force applied to a specific point of the body in animation?

Thanks a lot in advance!