Sorry, I was adding thoughts to my post while you were responding. Yes, I think the strategy is to start by commenting out stuff until you no longer get the symptoms and then adding it back.

I think your hunch about something not quite matching up may be right. I don't think it is the problem here but I remember once driving myself crazy over a bug that was caused by a single missing ; - for some reason the code compiled without syntax errors but line 2 was executing before line 1 and I couldn't figure out why... until I realized that Perl thought line 2 was a parameter to line 1 and so was evaluating it first. Sometimes Perl makes sense of things we rather it wouldn't.

Best, beth