Problem with setting the vector of pressure.

Hello,

I'm having a problem with changing the direction of pressure from normal to OZ axis. The program seems to be completely unresponsive to my commands. Below I am posting a short video of the issue. In the end the calculated resultant force should only have one non-zero component (Z). I would be very grateful for your help.

https://www.youtube.com/watch?v=DiOm7d-oQuI