OpenSim Stanford forward dynamics

[ThatCatLady]

I'm using OpenSim Standford for some research on the foot and am trying to find the force generated on plates under the foot when a single muscle is activated. I created pairs of stacked plates, where the top plate is attached to the foot bone I want and the bottom plate is attached to ground (ground is the pelvis in this model). The bones all have mass, gravity is turned off, and I have a control file that runs for 10 seconds and activates the muscle at t=2. When I run forward dynamics with force reporter is appears to work fine, but the plot of the muscle forces looks different every time. It also isn't giving me an option to look at the force in the plates. Additionally, I noticed that the foot is falling and the plates are going through each other before the muscle is activated, which makes no sense. I added the plates using contact mesh and elastic foundation force. Is anyone familiar enough with this software to help?