For the Static Structural Analysis
Under Analysis Settings, change the number of Steps to 2.
Edit the Force so that it is 0.0 N in Step 1 and 0.3 N in Step 2.
Solve the model and look at the contact pressure at Time = 1 and you will see that it is uniform along the length of the supporting beam.
The applied Force causes the contact pressure to become non-uniform.
For the Transient Structural Analysis
Is the contact status message a warning or an error? If you use a small enough maximum time step under Analysis Settings, you should be able to see the block break free and accelerate away. It can even leave the end of the supporting bar and begin to free fall.