Hi All,
I believe I may have found a solution to this issue. A bit of effort upfront, but it definitely works!
Lets say: Property A + Property B + Property C = Calculation Property X
For each of Property A, B and C, just create a new calculation property, maybe labeled “Property A Calc”, where you do (Property A x Constant 1) = Property A Calc. If Property A is blank, the Property A Calc property will be 0. If Property A is known, Property A Calc = Property A.
So then to get Calculation Property X, you would just do Property A Calc + Property B Calc + Property C Calc. Then it runs perfectly! AND you don’t need to do any workflows and you maintain the blank status of the original field which is important!