I have 3 computer added but only can select 2 computer in the top right of the parametric study tab (Maximum simulations run)  I can select all three computers in the "Run at" tab across the design points, but only 2 simulations at a time commence.  I have actually up to 4 machines capable of chopping my simulation time but am stuck scratching my head at this problem...

Everything is set up with my network monitor

Any help would be appreciated!