Word is spreading that much-delayed, megabudget musical “Spider-Man, Turn Off the Dark” is getting it together to begin Broadway perfs in October for an opening in November or December. And this time they really, really mean it.None of the parties involved would comment, but Marvel is said to have recently granted its fifth extension to the producers for the stage rights to the comicbook wallcrawler. Insiders say that in-progress prep work for the technically ambitious production has included a flying workshop that was held last week in Vegas and green-screen footage being shot in Gotham this week. Construction at the Hilton Theater is ongoing. There’s a possibility, it’s said, that an invitation may go out to group sales bigwigs in the near future to take a look at the work that’s been done so far. Ticket pricing remains up in the air. Over the past couple of months a cast has been re-assembled after previously announced topliners Evan Rachel Wood and Alan Cummings bowed out following the show’s delays. Jennifer Damiano (“Next to Normal”) is believed to be lined up for the role of Mary Jane with Patrick Page (“Dr. Seuss’ How the Grinch Stole Christmas”) tapped to play Green Goblin. Reeve Carney remains attached as the webslinger. Originally slated to begin perfs early this year, “Spider-Man” saw production halted in August due to what producers described as cash-flow problems. Music industry vet Michael Cohl came aboard as lead producer in November. An anticipated bow during the 2009-10 Tony season, which ended April 29, was eventually scuttled. It’s said Marvel has periodically asked for proof of the project’s progress, with some adding that the recent fifth extension would likely be the last. Capitalization costs of “Spider-Man” are widely speculated to have topped $50 million. One insider attributed a hefty chunk of that pricetag — as much as $15 million — to the added costs resulting from the multiple delays, as opposed to the admittedly enormous tech demands of the show itself. Helmed by Julie Taymor, “Spider-Man” has music and lyrics by Bono and the Edge of U2 with book by Taymor and Glen Berger. If all goes according to the current plan, the show will be open by Christmas.