The syntax is pretty easy to learn once you know how it works. Then it's a matter of learning what you mentioned, ie. functions, variables, etc. Then of course you can go onto learn about classes and other stuff, like the preprocessor, though I personally don't think that's essential. That should do you really, then you can start using the dgdk commands. I think it would be good if you learned some of the basics of the STL too, especially std::strings - they are a god-send to me
"It's like floating a boat on a liquid that I don't know, but I'm quite happy to drink it if I'm thirsty enough" - Me being a good programmer but sucking at computers