Missed all the other replies I thought that you posted on the 2nd of august rather than the 8th of feb.

To work out the effect of the weight of the beam the suggestion of calculating from the midpoint of the beam from the fulcrum is the way to go. The other way is to break the beam up into sections and calculate the effect of the weight of each section. The further from the fulcrum the greater the effect. The closer obviously the less the effect but when you add them all you will find that it is the same as working it out from the mid point.

As I said in my first post the weight and lever calcs will give you the force transmitted to the top of the cheese stack. To work out the pressure you need to decide on the shape of the cheese stack. The wider and flatter the stack the less pressure but the more stable the stack. The narrower the stack the greater the pressure but the more care that has to be undertaken in preparing the stack because it is less stable.

How would you be preparing the stack? Will you be using a press basket? Or will you be making up cheeses in cheese cloths stacked one upon the other?