Please help a frustrated newbie with his first site

Source files: https://filebox.vt.edu/~gyanez/flash_test/source/
main.fla is the one the loads in all other swf files

Website: https://filebox.vt.edu/~gyanez/flash_test/

I am having a series of problems with the site. here they are in priority:

(1) My site keeps locking up right after intro movie plays and the external jpeg is being loaded…Why? Do you guys see this too on your end when visting the site?

(2) My externally loaded jpg disappears after the mask finishes revealing it. Why? I only can get to this part on my Mac when I dont simulate download. If I simulate download I lock up during playback as described in (1).

(3) I am trying to use an invisible button over the externally loaded jpeg that when I roll over the jpeg a info text box rolls over the corner of the jpeg. However, it starts enabling the button before the picture is even fully loaded (causing the text box to float over the preloader, etc). How can I cause the button not to become enabled until the jpeg is fully loaded and mask has revealed it?

(4) Lastly. In the text box that rolls over the externally loaded jpeg I am also using LoadVars to load in external text. Well for some reason teh text in the dynamic text box dissappears during its animation…any clues?

Thanks. Sorry for all the questions but I am at my wits end.