Problem with formula

I am fairly new to syntax in crystal.  What I am trying to achieve is this.

I want to be able to write free text, something like this (I would only be writing in the code 821 etc...) I believe I can get Pack to be default.  Also row 1,2,3, etc... is coming from an access table for now which is in the report.

Row 1      Pack: 8218990  60/1.1

                Pack: 8218990  60/1/2

Row 2    Pack: 8218990  50/2.1

              Pack  8218990  50/3.1

I have set up parameters Pack1 and Pack2 to prompt for the information and these are set to allow multiple values.  I have tried to write a formula but this is failing

Could someone please advise on how to either fix the attached code or how to do this please.  There may be many rows or just one.

Thanks