Press 'F1' in shipmaker to get a full list of the controls.
Also, I should note for anyone building ships using SM, that rotated bits will look pretty blurry, and please,
please understand what you're actually doing when putting ships together. If you do it well, you can make some amazing things, but if you do it
badly, you can make some really, really
awful things.
Sorry to use you as an example in your own tutorial thread, sprog, but your submissions in the Caelus thread are pretty... offensive to the eye, to put it bluntly. Way too heavy on the doodads and internally disorganized. Use of the DST sections isn't helping; they're quite hard to use properly. Armoredcookie's clean and smooth designs, on the other hand, are a good example of a better design you can pull off. Once you learn how to do things like glow effects and such, though, then you'll really take off, and be able to do nice carriers and so many other things.
SM is a useful tool, but it alone does
not make you into a good shipbuilder. You still need to understand how to use it to make anything that looks good.
Read the Shipmaker Info & Help forum. Be sure not to mix certain styles as they go badly together. Since you're designing ships with it, don't be afraid to sign up on the forums there to ask for feedback from people who know how things work. They're quiet but we don't bite (much).
I should feel it's also worth noting that you could turn the Starfarer weapon mount sprites into a format compatible with shipmaker and apply them to a ship as part of the construction process.