How does it work with script

The mod does not work since 1.69. Gives error in BE-ExceptionReport.html
Recommended Action Mods were detected in the exception.
Close your game, try removing the mentioned mods below from your Mods folder and retry what you did when you received the exception.
If the exception does not occur then the problem is likely with that mod.
Check the mod download for any recent updates.

Possible Cause

(Confidence: 30%) My Script Mods\TS4HeightSlider6_original\Scripts\HeightModule.py
Reason Exception in Sim Timeline: Exception running Element (AttributeError: 'SimInfo' object has no attribute '_days_until_ready_to_age')

The script mod updated by Ted is the one that works. Anyone trying to use any other version can have issues. By the way. The mod still works with the latest Para Patch.

The mod works as expected. I am not sure what you are saying or what version of the mod you are using.

do you have to enable the cheat everytime or once only.

To use the mod, you have to first find the version that was updated by TedW. Then you have to have cheats enabled. Once cheats are enabled they stay that way until you turn them off. Cheats need to be enabled for the command to work.
The command is this:

Add_slider height 20 or Add_slider height -20

Pretty simple, and can be used on any sim, except toddlers. Make sure the sim is selected of course. You can use any value from 0 (default height) to 100. The minus sign is used to decrese height. It does not matter if you use upper or lower cases by the way.