I hope you used the .tmpl not .tmp1. If yes, did you try to restart the squid with the webinterface not with restartsquid and vice versa?
I think your
# Also are LARGE; make sure you aren't killing them as 'too big to save'
# - squid defaults to 4MB, which is too small for and even some sound files
maximum_object_size 4 GB
can be realized with the option "Max object size (KB) *" on Proxy --> Configuration --> Cache management.