IMHO they are the same as for any other software design fad: On a small scale, keep functions to about a page (80x24), and make them do one thing. On a large scale, organize things into modules corresponding to tasks. In your case, I would look at breaking a chunk of the script off into a separate module, which doesn't have to be in "I can has objects" style. If you later need more than one simultaneous instance of that module, you can always objectify it then.

Above all, don't get hung up on dogmas like "I need objects," "global variables are evil," etc. These are just vague guidelines, and are useless unless you understand why they are sometimes true.