Citron,
I have been tryong to dig up info on the Analogue Solutions AS0084 case and so far, have only found the Concussor User Manual which unfortunately, only gives you the AC power supply requirements (12-15 vac at 500 ma) and does not delineate the actual internal +12 vdc, -12 vdc, +5 vdc supply current output which is really what you need to make sure you stay under the supply maximums. It is not a good idea or statement to say, "The case will generally supply a full set of modules unless there are too many power hungry modules," because you have no idea what your power supply will deliver and therefore cannot ensure you do not exceed the limits of the supply.
So, we need to find out what that limit actually is. Without this, you cannot relly know what your limits are on you rack supply either thru Modular Grid or manually thru a spreadsheet or other means.
Go ahead and try your hand on building a virtual rack like yours on MG with the modules you have and go from there while I try to find out the power supply delivery. No wonder Analogue Solutions no longer makes these.