Just try to make something that you are comfortable with. I have only been using DBPro for about 2 days, but I can make a (very) simple 3D FPS game, and I have never used any BASIC programming language before! I have however, used GameMaker.
I found that looking at a few of the examples in the CodeBase and reading the forums a bit was a great help.
As I said before; try to do something that you want to do, so that you won't give up on it and you will enjoy making it.
One last thing; good luck!
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