You haven't any problem, select "Continue" in prompt dialog.
If you don't like that this is showed again change this value in (about:config)
Edit -> Configuration -> Browser Configuration, Search this pref in filter:
dom.max_script_run_time
Double click in it and change his default value from 10 to 20. (For example)
This is the time in seconds to run a Javascript code in a web site.
K-Meleon in Spanish