Product rendering with decals

 From:  plish (MPLISHKA)
4323.1 
Any thoughts on how to use MOI (which I love BTW!) and other renderers (I am using Kerkythea but am open to low cost-if possible-options), to place decals on a model? I am a newbie with regards to UV mapping and the like. Many of the product designs I do have labels on various surfaces. I'm stumped - any advice is most appreciated!
Thanks!