you can add an echo within a script to let you know if that line is even being reached. You can also include in the echo the values of different %variables or $1 or $nick or $chan to identify what those are. By leaving a trail of breadcrumbs, you can see where something went wrong. I usually like to include the scriptname and the line number in the echo, so if i forget to remove it, the echo message in status window tells me where to find it, rather than hunting through all my scripts for it. Something simple like:
echo -s debug: $nopath($script) $scriptline nick = $nick (1) $1
