Thanks for the praise. Sorry to hear you got stuck. Have you tried playing again since? I can think of two things that might have happened to you...:
1. RPG Maker had a 'visual freeze'. This sometimes happens when there's a hiccup with the game's processes. It causes the screen to appear frozen even though you can still move around and do stuff, you just won't be able to see it...
I'm afraid the only solution to this is to just try again, and try not to have too many programs running in the background or tab out from the game.
2. If you're using click controls perchance, they don't work right on every map. That particular area is one such place the click controls don't sync right so I would recommend using keyboard arrows and enter and suchlike.
Hope either of those things can 'help' you and you can continue to play the game!