I attached a quick example I made. It is simple but hopefully you can get some ideas from it. This is based on Lookout 4.5.1 build 18. If you have an earlier version you can modify the script and compile into the older version.
Quick note: if you enter a rate that exceeds 2%/second ramp you will not reach your intended % setpoint. This is simply because Lookout is not good at timing fractions of a second. You would want to offload any functions that involve fractions of a second into your logic controller.
The file works perfect for 1%/second or slower ramps like .1 or .01%/second rate.
Regards,
Tommy Scharmann