Using values from Lookup (Count)

I am struggling to use a value from another list. I have a lookup to a count related on a custom list to determine the number of projects per client. To be able to create a unique project number for each new project, I am trying to use that count related with a workflow to do something simple like the (count related)+1 = NextProjectNumber. I have everything else figured out except how to extract that value from the Count related.

I have tried workflows to copy to a text field, number, integer, … but nothing works. If I change my workflows to reference a field which has a value of 5 (for example) they are working perfectly but it just copying that Count Related field which I am struggling with.

I am a bit of a sharepoint novice so I may be doing things completely wrong.

My WF is something along the lines of

Set Variable 1 to Current List:Projects(Count Related) Do calculation variable 1 + 1 (set as:variable 2) Set Current List:Next Project Number to Variable 2.

Any assistance would appreciated.