It depends heavily on exactly what you want to make. The simplest weapon you can create with DRAY is the DRAY bomb - so simple, in fact, that you could easily make one by accident just by throwing together some DRAY, PSCN, and BTRY. The concept of "insanely complicated machines" is extremely vague, so I can't say anything specific. The most complex machines in TPT are subframe computers, and they tend to use DRAY for various purposes. You can find plenty of saves with tutorials on subframe computing, but I certainly don't guarantee that you'll understand any of it.

Most importantly, like any other element in TPT, DRAY is useless on its own and is only effective when combined with other elements and mechanics. So, without knowledge of the other mechanics, there isn't much you can do with it.