Script Trigger in Portal

Quick assistance.

I have multiple jobs that make up one project.  In a layout I am linking the jobs table (letter, envelope, etc) to the project table (Direct Mail Project) by using a portal and many hidden Tab Objects.  In the portal I have the following 2 fields:  JobType (letter, envelope, etc.) and the JobID.  In the JobType, I have a pop up menu and script trigger to select the appropriate Tab (letter, envelope) to prompt new fields for data entry.  My script trigger is:  

Go to Object [ Object Name: If ( isEmpty (Job::JobType) ; "Blank" ; Upper ( Job::JobType))]

Problem is twofold. 

1.  I can only get the first portal row to perform the correct lookup between the tabs.  Each subsequent one, will not.  Do I need to change this to a "Case Statement"?  Assistance would be great.

2.  For each JobType (letter, envelope, etc.), I have a specifications table with all of the field attributes that the JobTypes use.  For instance, Size, Page Count, Ink, etc.  Question, how do I prevent the same field attribute ("Size") data input from appearing on both the letters and envelopes Tabs?  In other words, I enter "8.5x11" for the letter size and the envelope tab shows the same thing.