I have just purchased my first resin car body- a NASCAR Impala SS  COT.  I am looking for any tips on how to trim the mold residue from the body, and recommended ways to work with and paint resin.  Since the body cost $35 I am not anxious to damage it.  Any hints on the  wonderful world of resin will be appreciated.

I can tell you one thing. A little sanding will go a long way. Resin is softer than plastic so it's easy to sand a little too much.

Wash it well to remove mould release - washing up liquid and warm water and give it a scrub.  Then let it air dry on a tea towel.
Trimming the flash out of the window holes will be real easy if it's thin - just punch through with a knife and carefully trim round the edges.
If it's thicker then drill a hole and cut it out using a round file or a fretsaw leaving a margin which you can file down or trim with a knife later.
Watch the dust you produce - you don't want to be inhaling powdered resin.

Best bet is to let the body soak in Bleache - White or purple power overnight. Some of the mold releases used like to repel paint. I haven't had a problem in years by just washing the body with either of these and not soaking but without knowing the particular make of the body that's what I would do. I've had a couple of resin kits that had the coats of automotive lacquer primer lift and flake off and lacquer primer is pretty hot stuff - likes to bite into most everything. Some of the Nascar resin bodies are pretty thick so you may have to thin it down on the inside.

 Yes you definitely don't want to be breathing in resin dust - it'll burn your nostrils. Always wash your hands after handling resin and work outside if possible.

Only use superglue for assembly as regular styrene glue won't touch it.

 The advantages of resin are that any bodywork or filler that you apply tends to go on smoother and not leave ghost lines behind like regular plastic.

Also you can use pretty much any type of paint on resin without a problem. Just make sure the resin is cleaned of all mould releases agents and grease from your skin. 

Mike