What events are you trying to grab?
From the help file:
The raw event allows you to process numeric server messages that are identified only by a number, and non-numeric server messages which mIRC doesn't recognize internally.
I don't know about you, but if I were scripting, there'd be a pretty good chance that I would try to grab events mIRC does recognise internally. (It would be nice if those worked with RAW to btw)