I like it! The cave-in / dynamite idea is really cool. It plays pretty well too.
I have one suggestion: switch up the hidden room with the idol so it has no treasure. That way finding that room gets you the idol reward, and finding the other one gets you the all-treasure award. Also, I'd set par/master times to around 2:00/1:35 respectively. My best time so far is 1:22.0.
I like the visuals. Good cave feel. I can only think of minor things you might change, like flipping the red barrier to be like the others (see below).
As for scripts and triggers 'n such, it would be possible to make a better effect for the cave-in and the explosion than just fading in/out the wall. Also, some of your messages are too long to fit in the display window, and should maybe be shortened somehow.
Anyway, thanks. Fun level.