Actually, I think the simplest way here would be to simply have a global float variable that keeps time, a global float variable that holds the current interval value, set llGetTime() into it each time a leaf drops, and just do an
Code:
if((llGetTime() - fLastDropTime) >= fCurrentInterval)
{
drop leaf,
set fLastDropTime to llGetTime()
}
In the timer. Then you don't need to do the value incrementing each time at all :>