I'm still not sure what you mean. Can you not use "exit
function" to exit the function  if a cell is false?

if blah blah then
exit function
end if

> exit function without altering the value from last recalculation
What value are we talking about?

This snippet...
With Application
.Calculation = xlManual
.MaxChange = 0.001
.CalculateBeforeSave = False
End With
.. is a recording of turning automatic calculation  off.

Also maybe you need to specify which type of parameter  you are
using.... ByRef or ByVal. They are both in help.