Thanks, Don. I do have a character (or characters) like that. Rosalyn, who won't show up in the book you're reading for a while, comments on the weirdness, from her point of view, of what's going on, and has to have things explained to her. In the "prequel," the Terran colonel who she is having an affair with, does research, although he still has his stubbornly "scientific" explanations for things. Oh, yes, starting in the middle presents it's own difficulties, but then, you're always starting in the middle. But her radio conversation with Jeb and her dialogue with Lido helps, and more comes along as the story progresses: a delicate balance, as you don't want to slow down the action too much, but you have to clue the reader in One thing I've done is to describe "around" something. What do I mean? Well, suppose you were writing to an alien audience about race relations in the US. You wouldn't come out and talk about discrimination in the criminal justice system, but you'd show a cop beating up a black man, just describing the two, not mentioning the race.
Another thing is to embed the explanation in the action. I don't explain that she shares her ancestor's ability to communicate and command the birds, I just have her do it. For those who are familiar with the Mabinogeon, the response will be 'oh, yeah.' But those who don't know the fairy tales will catch on from what's happening. The forest the fog the wolfen all evoke cultural memories deep in our collective unconscious. Other things have to be explained: why didn't Lido stick around to help her? So she flashes back to an incident that brought about the Treaty between Dragons and Men. It's a delicate balance. When she's on the pirate ship, I don't mention it's a pirate ship, just show that. Don't mention what they're oiling, the reader has to figure out that this is a society which wouldn't have motor-boats.
Also, again thanks for your review, some of your issues simply became Rhiannon's and Lido's issues.