To expand on @Julien’s excellent answer, I will note that we have a standing offer — if you get stuck on a file or project, send it in to us at support@carbide3d.com and we will do our best to help you work through it — many of the tutorials which are available are the result of such requests.
For the design aspect, you may find the following links of interest:
— obsolete with CC’s new corner options, but a useful tutorial on Boolean operations or doing this to imported or drawn objects
— very basic tutorial on drawing with the curve tool — also see: