You'll need to read up a bit, Kay, but the solution is to put the picture
into a layer, and change the visibility of the layer using behaviors. It's
worth checking out, because layers and behaviors are very easy, very
powerful features of FP.
Essentially, a layer is similar to a layer in Photoshop. It's transparent.
You can put an object on the layer and reposition it anywhere. That lets
you design pages that don't look like they're built on tables because some
elements are straddling the column borders. Layers stack "vertically" on a
Z-axis, so you can create some really neat (cool?) effects.
Behaviors let you modify many things on many events. What you're going to
use is a behavior that changes your layer from invisible to visible when you
mouse over the color chart, and another that does the trick when you click
it. Then you have to decide what event is going to return it to invisible,
and create a "restore" behavior for that.
There's a clear description of this in "Using Front Page 2003" by Colligan &
Cheshire, if you can find a copy. Other sources abound. You can even make do
with the FP Help file.
GRB