algo is singular
Algunos(as) is plural
unos(as) is plural
algunos y unos here: http://spanish.about.com/od/translationsfromenglish/a/algunos-unos.htm
I think there is a difference between the two words or concepts. "Desarrollar" means to take one idea and transform it in something real, something that can be used or built. It could be an architectural project, an engineering project or even a novel or any artistic idea. Develop is the concept. To take something that is in an embryonic phase and develop in something possible.
"Elaborado", means "built", you do things. Elaborate applies to manufacturing, is the process through it you build something. So I think that these two concepts are different, so:
Idea -> desarrollo-> elaboración.
You first think about a car, you make some drawings and then you pass to engineers to "develop" the project, then, the factory elaborates the car...more o less.