I was writing a script for my router and it wasn't being accepted. I was wondering how it is being validated and what the criteria is for a valid script. This is the message I was getting:
The field "sesx_script" is invalid. Please report this problem.
The script is pretty long and contains a user function, perhaps that's the issue? I got around it using a jffs file system and putting my script there which is called from the script indicated on the script page.