Move from SoA to ToB - confused (spoiler)

[Shine]

Hi
I think I'm missing something. Or missed something, rather.
I was playing toward the end of SoA when I found myself in the elven city and before I knew it, got carried along and ended up in ToB - the transition was rather cool

However, I'm not really done with SoA yet. I still have some stronghold stuff to finish and never did get to the Watcher's Keep. As I was playing I figured that I'd be able to get back to the Worldmap to return, but that doesn't seem to be the case.

Is this pretty much it for ToB, then? I thought it was possible to get to the Keep in either the game as well as the expansion. Can I get there later and, if so, can I get back to the challenge-room where that blacksmith-imp can make things (like Cromwell)?

[fable]

Once you've finished SoA, you can't return to the Keep or anywhere else in the original title. Sad, but true.

[kmonster]

You actually can enter Watcher's Keep later in ToB, but you won't be able to enter the regular SoA areas any more.
(The only chance to finish your stronghold or any other optional SoA quest is reloading a save from chapter6.)

You can get back to the challenge room later, many items you find in WK can be upgraded there by your imp.