I have a big workbook with many worksheets, and many formulae in it.
The problem (which occurs whether I have automatic calculation on, or
manual) is that since certain formulas work off other formulas, one of
them is updated before the other, and then the result of one of them is
wrong. e.g. I'll have a lot of DIV/0 errors since one cell referred to
is 0, but if I go into that cell and press enter to evaluate only that
formula (with manual calculation on) then it returns the correct
number. Then I can manually evaluate the division formula and it's OK.

Is there any help for this? Or anything to allow one to specify which
ranges are updated before other ranges?