House of sorrow and Creepshow Cassino - when is an action announced?

Hello, 
I would like to know if its possible to do the following:
1 - announce action (like KRC)
2 - tap creepshow cassino for stealth
3 - tap house of sorrow to untap cassino
4 - tap creepshow cassino again for stealth

The question popped in a discussion in the local playgroup because some people argued that once the action was 'announced' you could not play the cassino effect again, which I don't think that is particularly convincing because as far as I know I can play creepshow, seduction and any other modifiers that say 'only usable as an action is announced' in the same action. 

To summarize: Is there a window for 'when the action is annouced' that ends at an arbitraty point or can I keep playing cards until I'm done and them the action is effectively 'announced' ?

Thanks in advance!Name: Creepshow Casino
[FN:R2, Third:PB, SP:LB1, V5:PTo1]
Cardtype: Master
Cost: 2 pool
Unique location.
Lock as a vampire you control announces an undirected action to give that vampire +1 stealth, even if stealth is not yet needed.
Artist: William O'Connor


Name: House of Sorrow
[Promo-20081119]
Cardtype: Master
Cost: 1 pool
Master: unique location.
Lock to unlock any card you control that is not a minion. If you do so, neither that card nor this location unlock as normal on your next unlock phase.
Artist: Andrew Trabbold
 

The way sequencing works, you cannot use things during the as announced window except wakes and cards/effects that are to be used in that window. So after locking the Creepshow Casino, you'd have to pass the impulse and everyone else has to pass as well before you can use the House of Sorrow. At that point, the opportunity to use the Casino has passed.

I don't think this is about sequencing, because as acting methuselah you can play as many "as announced" effects you want.
www.vekn.net/forum/rules-questions/76645-actions-combat-for-beginners#87384

I see no problem using House of Sorrow to unlock and have an additional stealth from Creepshow Casino. The only restriction that comes to mind is HoS is not an "as the action is announced" effect, but these would mean I cannot lock The Barrens to discard and try to get a Seduction either.

The question is: Would House of Sorrow (or Barrens btw) end the "as the action is announced" window?

House of Sorrow and barrens are generic effect with no specific timing.

The only window when they couldn't be used would be "as a card is played" which happens even before replacing and is used for canceling effects.

So I don't see any good reason why HoS couldn't be used to use creepshow casino twice for thé same action.

Well, I agree HoS can unlock Creepshow Casino in that window. I'm not sure, though, that Creepshow Casino can be used twice there. See [LSJ 20081229] . Why would Creepshow Casino be treated differently than Tower of London? Is "as a vampire you control announces an undirected action" not comparable to "after resolution of a successful action"?

Also, Thiago has a point there. Playing a Conditioning closes the "as announced" window (you cannot play Seduction after it) because it is not an "as the action is announced announced" modifier. As House of Sorrow is also not such an effect (does not have the "as the action is announced" text) I would understand that using it closes the window in the same way. Basically, once you used it, too late for "as the action is announced" effects... But that means you cannot use a Dreams or a Barrens to draw a Seduction after you play the action? You have to do it before you announce?