I did (and do) this kind of compositing before, and without the plugin. Of course it wasn't as sophisticated and more time-consuming, but there's a lot of fun and control in it too.

The trick is based on the fact that RAW is a kind of negative that you can develop in several ways, and with the digital advantage that you still have the untouched (undeveloped) original at your disposal. One of the main reasons I went for the D40 as it has 14bit RAW, meaning you can go further in your manipulations. I usually set the camera to minus two-thirds of a stop. So I develop it several times at different settings (changing the general lighting, de-noising, using Bibble's Zones-plug in, even go completely crazy) and then, after saving as 16bit files, open Photoshop.
In PS, I use masks based on single or combined channels that I then manipulate with the darken and lighten blend modes. Lighten makes everything lighter that is darker than the grey value of your brush (or any pixel...combine greyscales evt. in separate files, then re-import as mask), darken darkens everything that is lighter than the chosen grey value. With some play and several layers you can achieve really stunning results.
More work, but 75Euro plus VAT is quite a bit of money for a plug-in. (I'm in desperate need for a new puter first as the laptop I now work with is ok but not up to what I want to do, so money is very tight).

There are no Borg. All resistance is fertile.