Halo 3 - Herioc Map Pack Problem?!?

[Hardcore Ben]

Okay, I Disconnected my Hard-Drive, Took it to my Friends house, And Put it on *His* Xbox, Then We Downloaded Herioc Map Pack (Because i Have Xbox Live on my Hard-Drive), It Took About 1 Hour.

When it Was Done, I Took it Back out and Braught it to My house, Put it in my Xbox (Elite)...

I Try to Go On Forge, And No Herioc Maps Were there!
Foundry Wasnt there, Standoff Wasnt there, And Neither Was Rats Nest! But then, I Sign in to Xbox Live - And all of The Herioc Maps are there!?

Whenever Im On Xbox Live, I Can Play On Them...
When Im Not, Theyre Not There!

Help Please, Desperatly - I'll Give The Person Witht he Best Answer As Soon As i Can.. Thanks For Reading, -Ben-

Dont Remove this Question, I Double Posted Because i Didnt Know what Topic To Put it Under, Sorry Yahoo.

 

[Justin A]

Mine does this, when you go into forge it only shows the normal maps, even after it says loading data/maps or whatever it says, but once it has, back out to the page before the map selection and go back in and they should be there, always does this on mine.