Running several renames in the same button still isn't a good idea in Opus 9. Since the new Rename Scripting feature handles most of the cases where people wanted to do that the problems with multiple-rename commands haven't been addressed.
Unfortunately, this is one case where you will still need to have two renames. This is because, at the moment, rename scripts don't have access to the file information fields (MP3 title, etc.).
Giving scripts access to those fields seems like an obvious extension and I've filed a feature request.
In the meantime I think you'll need a two button solution:[ol][li]Rename the file so its name includes all of the MP3 fields you need, with some kind of separator between the fields that makes it easy for part 2 to do its job.
e.g. A_Led Zeppelin_ D_IV_ T_03_ S_The Battle of Evermore_ E_mp3_
Doesn't have to be exactly like that but if the script can search for things like A...__ when it wants the artist name then its life will be easier.
[/li]
[li]The second rename would be a script which takes the name generated above and changes it as you want, applying titlecase (which you should be able to include as a subroutine in a larger script, to keep the logic tidy) to the song title part.[/li][/ol]
Someone might have to help you with the second part if you don't know VBScript. (I don't think I'll have time for a couple of days but I'll try to have a look when I have time, if nobody else has.)