These are not stupid questions at all, and we are working on better training materials as we speak. As you said, the need is definitely large for this!
There are some differences between the available versions of Dynamo right now. The older version (v0.6.3) is the latest stable release, and that’s what you have if you downloaded from the front page. The newer version isn’t officially released yet, but it’s about to be, as v0.7.1, and you can get the latest build from the downloads page:
If you’re just learning, use the daily build. In v0.6.3, you can forget about the transform by using an “Identity Transform,” which is to say, none at all, so that your rectangle appears in the center and in the XY plane. Pass the rectangle to a Model Curve node to send it to Revit. Basically anything that talks to Revit is in the Revit library.
In the daily build, there are several different ways to create anything–five ways to create a rectangle, for example, and none involve transforms. Though, you can transform (rotate, translate, scale) the rectangle once you have it. Using the daily build: