Couple Actionscript Questions

I’ve created a sliding thumbnail gallery that, when an image is clicked, enlarges it. What I want it to do is, if the user clicks the button to scroll to the next set of thumbnails, minimize any currently enlarged pics, then scroll forward. What happens now is: the thumbnails scroll forward, then the image gets minized. How do I make the function that scrolls forward execute after the function that zooms out?

For the same thumbnails, I have it set up so that when you mouse over a thumbnail the alpha goes from 60% to 100%. I do this using a Tween. Sometimes, though, while the mouse is still hovering over the thumbnail, the alpha instantly reverts back to 60%. It doesn’t happen every time, and there doesn’t seem to be any noticeable pattern of circumstances that cause it. Any ideas on what could be going on?

Thank you.

I’m using Flash 8.