As I wrote Ross, separately - in case anyone else sees this:
I haven't scoured the Help file to see if this is normal behavior, but I cannot imagine it would be. It's something that merely puzzles me - I can live with it, no problem - but I thought it might be of interest to you, as developer:
First off, I am running AM on a Mac - quad-core, 10.6.6, further config details below.
Every so often, I notice that when I hover my mouse over one of the drop-down menu buttons in a contraption's control panel, I see tiny green speckles slowly "growing," one by one, along the edges of that button. This fur, as I think of it, appears only when the Start button is On - when AM is running its sequencer, or whatever you call it (sorry, not sure of right term). The fur grows along the edges of these buttons, as you can see in the attached Grab images.
I have not been too scientific in my observations of this phenom. so cannot tell you exactly which contraptions or circumstances are involved. But I can tell you that the fur disappears if I click onto another contraption's panel. And it staerts growing only when the cursor is hovering on a button; once started, though, it will continue to grow even if cursor is moved off button.
Right now, I have an Arpeggiator open and there, fur is growing as described. If, though, I click on a Bassline in this same patch setup and hover over its time grid selector (? - 1/16, 1/8, etc.), no fur.
When I click away from, aka deselect, the Arpeggiator, any fur I've seen grow there disappears, instantly; when I come back to that contraption, though, it starts growing again (if I put cursor in right place). I also notice that these furry speckles grow in some kind of regular, seemingly rhythmic pattern, almost as if they are mirroring AM's timing or pattern info! Also, if I stay clicked into Arpeggiator, start some fur growing on a button but then move my cursor elsewhere, the fur keeps growing - as long as I keep Arpeggiator panel selected. Finally, if I grab the green bar at top of that panel and move the panel, any fur in that panel disappears immediately.
The first image below shows an extensive growth of fur, with faint lines connecting the fur on top and bottom edges of the menu button.