I'm not sure whether to hope Hollywood recognizes the themes of the Deryni series, or hope that they don't! It's a sort of "damned if they do, damned if they don't" proposition, most of the time. Sometimes they don't recognize the themes of the story at all, but if they manage to capture as much of the surface storyline, basic conflicts, character interactions, etc. in the film as in the original book, then at least 80% of the original essence of the story will get through, and astute viewers might still pick up on the subtext, or at least be intrigued enough by the movie to go out and buy the books, and will discover the subtext there.
That is what I'm hoping for with the Deryni film(s), because in my opinion--given recent Hollywood offerings--that would likely be our best case scenario.
Sometimes, though, Hollywood says "Oh look, here's a cool and culturally relevant theme! But it's subtle and we can't count on 100% of the audience getting it, so we'd better glitz and glam it up, take out all this 'unnecessary' stuff in the story ('unnecessary,' that is, to pushing their agenda, though
quite necessary to the story if it's to remain something resembling the original, fully dimensional story and not just a delivery mechanism for an agenda!), change the characters a bit to 'modernize' them and make them more 'relevant' to today's audiences, and make the theme so glaringly obvious that even a toddler fresh out of diapers will learn The Moral Of The Story!" And then you end up with a story that either slams you with an agenda to the point of killing the story ("Happy Feet," which starts out as a fairly sweet 'children's' tale--albeit with some awfully adult subtext!--about penguins trying to attract mates, but eventually devolves into a rant against commercial overfishing in Antarctic waters that had some young children--my own daughter included--traumatized, leaving the theatre in tears and vowing never to eat fish sticks again!), or you end up with filmmakers inexplicably forgetting what the original story was meant to be about in the first place because they've had "Better Ideas." (For one horrific example, compare the book version of
A Ring of Endless Light with the TV version:
http://en.wikipedia.org/wiki/A_Ring_of_Endless_Light vs.
http://en.wikipedia.org/wiki/A_Ring_of_Endless_Light_%28film%29 ). Now, I happen to love dolphins, and as an impressionable young teen, the book version of
A Ring of Endless Light briefly made me consider a career in marine biology. But it's first and foremost a book about a teenaged girl's struggle to come to terms with mortality, not just a "save the dolphins" story, and to strip away all of the rest of the book's message to reduce it to that both demeans the original novel and its intent, and alienates viewers (this one, anyway) from the "New And Improved Theme" the filmmakers tried to make it all about instead. That's what hammering viewers with any theme tends to do, no matter how worthy the theme might happen to be.
And that's what I'm desperately afraid would happen to DR and the rest of the series, if Hollywood starts to see the series as "stories with a theme" instead of just "really cool stories we could do some fun special effects with." I'd rather have the audience see the stories on screen as close to the original books as Hollywood is capable of depicting them, even if that only deals with the 'superficial, surface stuff' of the books, and hope that at least 80% of the underlying essence gets through despite the filmmakers' blissful unawareness that it has any sort of "theme," and that viewers are left wanting more, go out to buy the books, and KK ends up filthy rich off the royalties.

Otherwise, call me cynical, but here's what I predict will happen if this film ends up in the wrong hands:
"Oh, sweet! Here's this great Deryni series of books that's chock full of LGBT issues; that's certainly timely and culturally relevant, so what can we do to crack that up a notch and make sure the audience doesn't miss the point? Well, let's see...sure, this is the coming-of-age story of a boy king who is learning how to be a man and rule wisely and well...yadda yadda...ok, that doesn't really serve the agenda, so we'll downplay all that, but look here, here's a really compelling character in this Alaric, and he's one of those misunderstood Deryni, and he's got LOTS of freakin' potential...yeah! OK, so just to make sure folks get the point, he's not just Deryni now, he's persecuted because he's Deryni AND he's gay...oh, wait, you say there's a wife coming up in the later books? Well, no problem...'Richenda', 'Richard', no one's going to know the difference unless they've read the books, and they came out years ago...what, the 70s or early 80s? Yeah, so 'Richard' it is, because s/he's just a bit character anyway. So, Alaric's our hero, and he and his cousin Duncan are off to save the day, and...oh wait, we do need to write this Kelson chap in a bit, right? OK, so that's our subplot now. He's a boy king, so let's make him an angsty dithery sort, because strong leaders who know their own mind are SO 1960s, and we're not out to write about decisive men like Thomas More anymore. Even the New and Improved Aragorn and Peter of Narnia had to learn how to dither and be J. Alfred Prufrocks*, because we can't have strong leaders presuming they know what they're doing without having to angst first...if they dared to wear the bottoms of their trousers rolled, they might disturb the universe! So this Kelson...he'd be insecure too, much more so than he was in the books--that's more realistic and relatable, you know--and the great climactic point of the film can be when Kelson grows enough of a spine to stand up to Loris and have this showdown with lots of fireworks...what do you mean, Loris isn't in this movie? Well, it can't be Alaric vs. Charissa, because if Alaric's gay, there's no chance to spice that duel up with sexual tension and lots of innuendo for audiences to giggle over, so let's just chuck her out of the script and bring Loris in a bit early. Unless we want to change Charissa to Charles...."
I'd like to think that's over-exaggerated for comic effect, but then I go back to the differences between the book and film versions of
A Ring of Endless Light and I really have to wonder if I trust Hollywood to "get" this series at all. Since I don't, I'm hoping they'll stick to what they do best when they bother to try harder--telling a decent story that bears at least some strong resemblance to the original, with some decent special effects, and enough substance to make the viewers want to rush out and buy the books afterwards. *sigh* They might not have "nailed" the full essences of
Lord of the Rings, The Chronicles of Narnia, or Harry Potter either, but at least they attracted more readers to those series, and if the DR film and any subsequent ones can manage that instead of alienating potential readers by being too hamfisted and so off the point that the original stories can't shine through, then I'll be content.
*For those of you whom I just lost with that literary reference, here's what I mean by "Prufrock." I swear I think of this poor fellow whenever I watch many of today's modernized angsty-dithery "heroes" on film.
http://en.wikipedia.org/wiki/The_Love_Song_of_J._Alfred_Prufrockhttp://www.uvm.edu/~sgutman/Eliot.htm