Avoiding mouse polls

[Ken Norris (dialup)]

Sceneario:

Single switch adaptiveware. Works only with mouse switch messages, no
buttons.

I have objects which hilite (not really, they just change pictures) in a
sequencial loop. I want to choose one so I click when it's hilited and that
causes further actions/choices.

I can't see any way of doing this without polling for the click.

Ideas?

TIA
Ken N.