Help with stupidly hard quiz

[ApocalypseNowt]

Each year my work does a stupidly hard quiz. There are many stages and we get a month to try and do it.

Anyone help me with this stage? there are 21 pictures of celebrities and I've managed to work out who they all are but now I'm stuck on working out the password to the next stage. Each picture has a coloured Roman numeral in it so I assume I have to use those to work out the answer...

BOOM! 4691 is the answer!!!

Is that using Regulators instead of Gunslinger?

Yes it was.

Hurrah!

It was written under a pseudonym.

@SoupDragon - just discovered that Billy the Kid's gang were called the Regulators!

Aha!
Recalculating...

4691 with The Regulators?

Sorry - cross posted (too slow)

Well done @SoupDragon

Next stage is a crossword. Looks like the answers are all names of bands

Inspirational goddess is Muse

Five in religious houses is “chvrches”

Manson Family Member might be Kasabian

Underground river is Styx. I didn’t know they were a band.

Number 24 = They might be Giants

Town in Somerset is Portishead

For "I've got it!" There seems to be a fairly obscure German band called Eureka but that seems doubtful.

UFO's might be Starship?

I thought that but was unhappy with the plural of UFOs.

Fashion Magazine - En Vogue?

23 - Muse

Release from the cycle of rebirth is probably Nirvana - I can't see which clue goes where on my phone.

Sindarin Horror is Gorgoroth (a Norwegian metal band apparently)

Misheard Beatles lyric is Tangerine Dream

The faashion magazine is Depeche Mode, not En Vogue.

18th c agriculturalist is Jethro Tull

10 - Paramore? I've never heard of them but the do indeed exist.

Apparently there's an icelandic band whose name means victory rose - Sigur Ros. Not sure if that's too much of a stretch...

@SoupDragon yes I was bit about the plural re UFO's!