Looks really cool. The town, especially the narrow streets do make me wonder how playable the board is. Were older versions of Warhammer, for example the herohammer phase a lot more skirmish based? I can't imagine playing a game of 8th on that board.
Not that I know of, maybe that chap just got a bit carried away in making scenery that it became a bit impractical to use it for a game but otherwise amazing. Maybe the scenery pieces were magnetised or something to allow for easy removal during a game. We'll never know, as it seems that he stopped being active a long time ago...
I doubt the terrain is glued to the table; he probably just piled it all on for the pics. Were I to play a full WH game on this board I would probably pack the sides of the board with some scenic terrain and possibly scatter a few things in the center to provide some clutter/cover. Then again all the terrain would make a good skirmish game if that is what he was going for.