You already have the mIRC Scripters Bible (aka the Help file)

You'll find most of the commands used in there.

mIRC scripting is it's own language. You can't take an mIRC script and use it with another scriptable IRC program (I''m presuming that there are others) without some modifications.

Some of the commands used in mIRC scripting are made for mIRC and mIRC only.

As to what you're looking for regarding the deop code
Code:
 on *:deop:#:{
if $opnick == $me {
.msg $chan $nick thanks for deopping me!
}
}

Please note that the display may not show properly, due to lag times between your client, your server, the client that issued the actual deop command, their server, and between your server and their server.