Yup I have the exact same issues with mine. For whatever reason, certain tables seem to be limited on what you can enter into them. I found this on the line pressure table as well as some other weird engine tables too.
I was going to post this same question over on HPT forum but never got around to it.
EDIT: I just started a new thread over there about this if you care to see or join in with me.
http://hptuners.com/forum/showthread...1952#post41952
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