In the program the color scale being used is pink where there is maximum compression, and blue where there is maximum pull. But it's a bit difficult to get a clear picture of the forces involved because of the scaling. I just found a menu where you can change the colors to make it a bit easier to see the forces. Green shows the lowest forces in the tubes, when red is the highest.
The picture shows the most stressed tubes in the frame when it is being twisted. This picture isn't related to material thicknesses used in the model, it just shows how much force goes through each tube. As you can see the colors in the roll cage are nice and even, so not that much going on there.
The tubes that have to work the hardest are the R tube and the tubes around it on the right side of the engine bay. The triangulated structure seems to take quite a bit load off the left side. If only we would be allowed to have two R tubes. The loads in the prop shaft tunnel tubes should be sorted out once we get the panels added.