At least for the FCX line we were told when trying to open a support
case that the limited lifetime warranty only applies to hardware and
does not make you eligible for any kind of support or software beyond
getting hardware replaced.
Yeah, you need to buy "phone support" if you want that. It is the lowest level of support and still pretty inexpensive compared to other vendors. In other words, 5 years of free hardware support and 5 years of Remote "phone" support (under $300/year I think) isn't bad when compared to annual support costs for other gear in that class.