1. Robo itself (himself, i guess) doesn't have access to Shadow Magic, it's only said that his laser weapons produce a Shadow Magic-like effect. Just like how Crono's Slash tech produces a Lightning Magic-like effect without actually being 'Magic'.
2. The Elements are not artificial. They are processed and refined, but they are originally something close to an ore that comes from the earth at points of the earth called 'power points'.
Good points. When I meant artificial I should have said that Elements are used by non-innate users to access Magic. I had forgotten that they came from ore, and about Robo's weapons. Of course, hydor-electric power comes from nature but requires the use of artificial means like dams. And in the case of Elements, Grids.
Conmsidering the level of technology in 1020. A.D. Grids and Elements can't be that hard to make. Humans had learned how from the Dragonians so the making of these Dragonian devices may just a particularly difficult craftskill. Considering how little is said about them it is hard to tell.
It may be a "Gameplay" aspect but I always wondered how monsters were able to use Elements without Grids. True, they have Grids in battle but I really mean is the physical device that allows people to use Elements. Remember, Mel steals Kid's Grid when she is sick. Monsters uniformly use the same Elements in battle so having an actual Grid like the parties is unlikely. (And wierd. How could a Gloop wear a Grid?) The Grids may be made of a particular type of ore that focuses the energy of Elements. Tech skills in CC may be developed by characters through practice with their Grids since in the game more Grid Space and most Techs are learned with Star levels.
Monsters draw on Elements naturally because they are Innate Magic Users. Even party chracters can access the elements like V-Translanka mentioning Slash. To support this, most Techs seem to be derived from the character's innate abilities like Marle can use Aura to heal, a common ability in most Blue innates in CC.
Maybe the reason that party members have these abilities from the onset is that they are innate magic users or that all humans that are sufficiently evolved (through Lavos's interference) to utilize Magic. After all, few creatures from 65 Million B.C. in CT could use special attacks and relied on brute strength with the exception of Terrasaurs, the Volcano-type monsters and the Dark Tyrano.