Here are my responses to your queries/observations.
A2) You can check the minimum and max values from on the panel on the left side, Although as the contour or the vector display is on the mesh elements, unfortunately, there is no better display available there.
A3) The Force variable shows all the forces generated in the selected region. The Vector display shows the Force vector(arrow). You can alter the number of vectors displayed from the appearance options.
A4) I’m not sure what could be causing the slowdown. Initially, the solver may take some time to solve and display the results. I was able to run the files shared at a fairly good speed. I don’t think there is any way to turn off thick shell representation. I will need to check this with my team.
B1) With one bolt for all locations option the value entered for the axial load will be divided for all locations. So if 135kN is input it will be 135/x kN for x number of locations. So correct value for your simulation would be 26*135kN.
B2) I think that is a 0.1% inaccuracy due to meshing and other factors of FEA and it can be ignored. Although I can check back with my team on this.
B3) You can turn on/off mesh at any point during the workflow using the “Show mesh” option on the top right.