Yeah, I think both "Chapel Of Love" and "I've Got The Music In Me" might have been recorded, but there never seems to have been any real confirmation. As for "Moviestar", she was just a backing vocalist on Harpo's single. There's no way she'd have been able to use it as one of her own B-sides.
Honestly, I think selecting the B-sides from Frida's second album is spoiling too much of the portion of the album; one of the better suggestions could be a single where Frida is in the A side and Agnetha is in the B side, but I'll relent with this :-)
Fernando / Tropical Loveland [Swedish version – per a fan's [me] theory.] Som en sparv / Skulle De' Va' Skönt Aldrig Mej / Jag Är Mig Själv Nu Ett Liv I Solen / Ett Liv I Solen (a cappella, or vocals only)