http://www.highrez.co.uk/downloads/XMouseButtonControl.htm
^ that one is a really good one that I use whenever I am mapping my mouse keys.
It works!
too bad it replaces middle-click (open in new tab)...
By mapping the action to a different layer, you can change the settings so that the mapping is done only when you want it to.
Here's how:
Double click the icon for the program in your task bar.
Go to Layer 2 in the tabs and change the settings as needed (make sure that Layer 1 has no actions associated with it. Save.
Now right click the icon for the program in the task bar.
Go to Layers and select Layer 2.
Play Elements without having to press the spacebar.
When you're doing playing Elements, right click the icon for the program in the task bar.
Go to Layers and select Layer 1.
Switch back to Layer 2 when you're playing Elements.