Solver for Production Planning

I have been playing with solver for over 2 weeks trying to figure out how get this spreadsheet to calculate the best combination in each column and row and get the lowest cost possible.

I know how to use excel quite well, however, this problem is well beyond my capacity.

Could someone please take a look at the worksheet labeled "PP" in the attached workbook and help me estabilish a functional way to reduce the total cost while satasifying the constraints.

The constrants are outlined in cells H20:W20 in the form of a formula. An error will show as an "Err" indicating a problem with the current configuration.

Briefly, the conditions are as follows:

OT <= 1/2 RT
Sched. Hours <= Capacity Hours
Total Scheduled = Production Requirements

If your looking for a challenge I would recommend attempting this as it has taken so much of my time already and I KNOW its possible but I just cant wrap my mind around it.

I have manually input one possible answer, however, this is undoubtedly the best solution. And I would prefer to automate the process as it takes a lot of time to complete with just trial and error

FYI...To avoid confusion, I have intentionally hidden the other worksheets in the workbook, but if it helps you can simply show them in developer mode.

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