Okay, I'll admit that I started composing a reply yesterday, but reconsidered. I have an opinion, but not a very well-informed one.
I haven't read the book you mention. I did make it through The Name of the Rose and Foucault's Pendulum, but I found them tedious. They picked up a little momentum as they went along, but for me, not enough. I remember thinking that he could have said the same thing more clearly and even more beautifully, with a lot fewer words. I enjoy all that pretentious intellectual semiotics crap as much as the next guy, and I enjoy quoting philosophers and using words like postmodern and deconstructionist. I've even read Lyotard and Derrida. I've read some others who were harder to read than Eco on an intellectual level--Hegel and Heidegger seemed particularly impenetrable to me. But I still enjoyed them more than I enjoyed Eco. Maybe it is the translation, I don't know. I sometimes think these writers are just thinking out loud, publishing what really amounts to a rough draft, and what we're reading is not really ready to be read.
I hate to abandon books too, but there are a few that I've set aside, thinking maybe I'll be more into it someday, or more willing to slog my way through the prose. My two cents worth is that if you aren't enjoying it and don't really have any need to read it, I'd shelve it.
Not much help, I know. I just didn't want you to feel ignored.