Flash 4 problem

I have a fairly simple project that I am working on in Flash 4 (maybe that’s the problem) and it is driving me crazy.

In a nutshell, I have 12 PNG images with transparency that I have converted into single frame movie clips. The 12 movie clips are divided into 3 categories and there is a button for each clip. When a clip’s button is pushed that clips alpha is changed to 100 (to make it visible) and the other clips in that category are changed to 0 (to make them invisible).

The very bottom layer is a background image. For some reason when I add the last 1 or 2 movie clips (with an alpha of 0) to the timeline the background image will not show. Also the last button of the 12 does not work. However, If I move the layer that that button controls higher in list then the layer that takes it’s place does not work. It’s hard to explain since I really don’t know what’s going on.

I just discovered that if I move the bottom layer (background image) up two levels everything works perfect except the two layers that are now covered up by the background image. Is there a set number of transparent images that you can see through?

Here is a link to a directory with the files. If anyone would care to take a look at it, I would greatly appreciate it.

http://www.flow-rite.com/temp/

Thanks,
Tim Miller
www.1989batmobile.com