issue with GaitLowerExtremity

Hello everybody.
I’m currently trying to simulate a gait trial to determine knee joint reaction forces. We have identified a small problem with a non-ideal marker set so far, but there seems to be a bigger issue too. When we simulate the gait, the knee forces amount to far more than realistically possible (about 30 times %BW). We believe that small inconsistencies with the marker set cannot be the source of such a huge difference in results, but we seem unable to identify the real reason. Any push in the right direction is greatly appreciated.
V.T. Nguyen

inaccuracies in the motion will of course result in strange results, but you can check some basic stuff.
Please make sure gravity is applied in the right direction, I guess it should be in -z direction?
Please remove all muscles and have a look at the joint moments and control especially if you apply the right forces on the right foot and if the center of pressure makes sense. etc.
Best regards,