Light

I have no idea if this is one or two dresses, but it's shown with different accessories in the movie.

First, it's worn with a 'smaller' necklace and a belt...

and then it's worn with a wider necklace, without the belt.

The seams seem to be pretty much in the same places on those both versions as well as in on the dress sold by the Propstore (see below), so I assume that this is all one and the same dress:

Some more unsorted pictures of both versions; more costume analysis below:

This is one of the two outfits, as offered by the Propstore of London.

Note that the 'headpiece' (first picture) doesn't seem to belong to the costume shown in the movie, except if it was completely covered by hair. Also note the snaps on the backside, next to the zipper. I suspect that the 'scale spine' jewelry Dame Vaako is wearing in the movie was attached to them. I also suspect that this 'scale spine' is originally attached to the necklace, which is missing in this costume sale.
The shoes were obviously - see shoe label - made by Peter Fox and then covered with the latex-covered netting of the gown.
I assume that the material is indeed latex-spotted netting; this can be quite clearly seen on the 'hand' closeup by the Propstore. Note that the 'glove' is one piece with the dress.

All in all, this costume is quite simple as long as you keep the correct seam placement in mind and don't fear manipulating netting fabric with Latex ;-) Most of the latex-spotted netting is probably lined with a skin colored fabric... except of the sleeves.

Light-Dark

This is basically the above described 'light' gown, just without sleeves and the netting backing is darker than the latex 'patches' on it.

Aereon Confrontation

---cool costume! Corset-style, platinum colored neckholder bodice, adorned with what seem to be flakes of golden metal. Note the placement of the bone casings, which clearly denotes this costume to be corset style (the bones don't go up all the way to the neckholder).
Also the side hips have been cut separately, giving the optical illusion of wide hips and small waist.
The standing collar clearly shows the bones that have been worked into it; it's made from platinum colored organza.
I assume the spine motif is covering the lacings that go up the backside of the bodice.

The skirt is front split and decorated with what seems to be ruchings of tattered organza in greyish-golden-greenish color.

Dame Vaako is wearing pointed shoes with this dress.

Battle

According to the Riddick insider information on the Director's Cut DVD, this dress became known as Dame Vaako's "Battle dress".

It seems to be made from aged black leather, painted with gold. The decorations on her bodice could be real metal motifs that were sewn on, metal flakes that were glued to it or they could simply be painted on (which I doubt, because there seems to be a structure in them).
The bodice is corset-style, again with the side hips cut separately, just like on the 'Aereon confrontation' dress.. This, however, is not a neckholder style bodice, but clearly a corset with sewn cups.
The necklace is also attached to the very wide spinal motif on her back.

The whole ensemble much reminds me of Padmés corset dress from Star Wars, Episode 2. The shaping of the skirt is also much likely as well as the fingerless gloves, which, however, don't go as high as the ones on Padmés costume.