I'm working on a sensitive document, so I'll try and explain my issue as best I can. I didn't create this document myself - the company I work for has asked for a modification, and if I can figure this out it would go a long way to completing that modification.

There's 2 columns;
A - will contain a 1, 0 or x depending on responses elsewhere
B - will contain a comment based on responses elsewhere

It uses this formula to create a score for the section;
=COUNTA(B2:B20)-COUNTIF(A2:A20,"x")

What I need is a modification to the formula if, for example, rows 4-8, 11, 13 and 18-20 were not required for a specific customer. So the formula would only contain (from both columns A+B) rows 1,2,3,9,10,12,14,15,16,17.
I can't simply delete or reorder the questions for a number of reasons - namely how they relate to other sections of the document and how it gets imported into our software - and that the same template is used for multiple customers and it's only specific ones where this difference is required.

Our software can hide the questions from view - however it will still take the score based on all questions.

I've tried just selecting the relevant cells, but I get the "too many arguments" error.
I've also tried the formula like this;
=COUNTA(Range2)-COUNTIF(Range1,"x")
Where range 1 & 2 are the required cells from each column. It worked with just Range 2 - i.e. =COUNTA(Range2)-COUNTIF(A2:A20,"x") although I don't think the score was accurate. When I put both Ranges in I get "#VALUE!"