What you describe is certainly possible, although I couldn't tell you how to setup the standalone Maximiser because I've never used it.

It's probably even practical to a certain degree, but I don't really understand why you wouldn't want to go with a key broadcasting solution instead of relying on mouse clicks. There are free solutions around, if cost is an issue.

If you play on a single machine, don't forget that you'll actually need three clicks for each icon you want to click: one to get focus, one to perform the action, one to get focus back on the other window. You could reduce the number of clicks by globally enabling Focus Follows Mouse, but that in itself is fraught.

Have a look around the Software Tools forum for software broadcasting solutions. They really are your best bet.