I'm using the "Back" easing function within the Smooth Motion ScriptFX for a logo move. However, the motion doesn't overshoot the final position nearly as much as I'd like. I've looked at editing the script - but it's way over my head. I can do some simple Actionscript and After Effects expressions, but Lua Scripting is beyond me. As far as I could see there was no parameter to adjust for how much the Back function overshoots the final position. Is there a way to do this without having to be a programmer?
I'd suggest adding another function that does what you want to the table of easing functions accessed by the script. It should be apparent from the Script FX source where this table is located. This would introduce a new option in the UI which you could then choose.
But such an addition wouldn't be portable and travel along with the model file - you'd need to install the same modification on every system you'd use. Keeping all your modifications within the Script FX source itself would allow it to work anywhere, so a better solution might be to hardwire a custom easing function right there in the script source.