Oh excellent! Consider yourself my bestest online friend if that happens! 
Even if it does a simple edit, save, line numbering and syntax highlighting it will be hugely beneficial. I wish i could "beat you to making it" but unfortunately i don't know my .dll's from my .sys's.
[quote="newguy"]Thanks for the explanation, sweetfunny.
I never really use the preview pane in Opus, since I always have a single dual-pane lister open. But I can now see how having at least code highlighting could be useful in your situation... [/quote]
No problems, and yeppers when you spend a ton of time working with certain filetypes you really appreciate the ability to view, edit and manipulate them in the fastest and simplest way possible. Switching in and out of a third party app so much is nowhere near as efficient as viewing/editing them inline in Opus.
I really like Leo's NFO Viewer Plugin it does a similar thing, allows you to view a properly formatted NFO without needing to launch a text editor and i only view a handful of NFO's a week.. So a text viewer for other filetypes will be super useful.
With how you have Opus configured, with no preview pane then something like this wouldn't have much purpose. I have Opus like this: i42.tinypic.com/30u8pbb.png
I can up/down arrow to highlight files, preview (and eventually edit) in the right pane. My setup is nothing flash design wise, just functional.