You shouldn't use ANYthing oil-based on SD, whether cosmetics, 
pastels, etc. Because SD are a polyresin they are a plastic & resin 
bonded. Plastics/vinyl can (and often do!) absorb oil-based 
products, which over time (minutes-> years) bleed into the plastic 
component and spread. You could end up with a big blotchy mess >_< 
(Believe me, I've seen it! yuk!) It will saturate into all levels of 
the material.
Use chalk pastels or powdered human cosmetics on the resin, or 
acrylic paints only.

Note: Volks RECOMMENDS Mr Super Clear to keep your SD clean and to 
prevent yellowing of the resin. There is no similar substitute in 
the US, as the contents are illegal to sell here. The 
general 'fixative spray' you will find in US art or craft stores is 
not intended for resins or plastics, it is usually made for *paper*. 

If you are blushing your doll (or even just a face-up) you will need 
more than one coat. Volks suggests 2-4 coats. Particularly with 
powdered coloration this will be neccessary. I would be highly 
suspect of furniture wax or anything not intended for use on resin. 
The chemicals could combine in potentially toxic forms, as well as 
change the chemical composition of the resin, or cause 
discoloration. I have 3 SD coated with Mr Super Clear, they have 3-4 
coats each and suffer intensive play including trips outdoors. (hey, 
its fun! XD) I do not have ANY problems with cracking, peeling or 
rubbing off on the coating after over a year. And I handled my dolls 
quite a lot in the process of coating, as I was applying chalk-blush 
at the same time. As with ANY type of sealant, certain things may 
scrape it off; ie sandpaper, rough concrete, metal edges....friction 
between joints. These would also scratch the resin if unprotected. I 
think that sueding the joints may help in this (plus it aids 
immensely in the posability of the SD, probably 10 times that of 
wiring).

When coating:
A. make sure the temperature isn't particularly cold/hot or humid
B. shake well!
C. Spray from a distance 8-12" away
D. spray in a continuous motion over the part and SET THE CAN ASIDE. 
The surface will appear slightly shiny. If you see a film over it, 
you held it in place too long. It should dry within 5 seconds, if 
not, you put too much on. Wait 15-20 sec. at least before 
reapplying. Reapply 2-4 times.

Marta/astrosnik