I dont know if you solved your problem, but here we go.

toolbar n1 <name> <"tooltip"> <path-to-icl.file\example.icl> <"/command">

The n1 tell mirc what icon to use from the *.icl file, and this working for me, windows 7 32 bits, on mirc version 7.19 .

if ($me != tired) { return } | else { echo -a Get a pot of coffee now $+($me,.) }