[pkscout]

One thing you could try is to have a hidden skin setting with the version number. Then use a conditional to check that setting against a string. If it doesn't match (and empty would count as not matching) then run the script and save the updated version number to the setting. I do something similar for my Estuary mod, although I only load some variables, not run a script. The only thing you have to remember to do is bump the version string in the skin where you do the conditional.