change to screen rules - Cause hanging?

The other day,  as users went into our system,  everyone was getting hung up or could not even get into Lawson.  We tracked it down (we think) to one custom program.  We re-compiled it just to see if that would work. 

Then in our test environment, we managed to get it to hang once and then we decided to do an srgen (because of an odd message one user got).  After that, we could not get the system to hang again.  We had made an additonal screen rule, but we had done an srgen the week before.  The offending program actually does not use that particular screen rule.  So,  we did go ahead and do an srgen in production and after that no one experienced any issues.   I am having a hard time believing that is the problem,  but has anyone else ever experienced that ?  I am wondering if, now that we are using Portal alot more,  if we are skipping a vital sequence when we compile programs and move them to production.  Do we always have to do an srgen, xscrgen, tranxml and then a compile when we move a program to another product line?