More charitably, this is the way all research prototypes work in any field.
Production vector illustration packages hire a team of people who spend man-years of effort canvassing customers, collecting bug reports, adding features and affordances and refining the user interface, writing documentation, and so on. Someone making a research prototype where the UI per se was built in a few weeks is not going to have the same feature richness, level of polish, or clarity of outward-facing documentation.
Give it some time.
Part of why I put it up with no instructions is to get feedback on how intuitive it is to use without any explicit instruction. I've gotten mixed response; some people seem to get it, others don't. So thanks for this bit of feedback. There's a basic help panel now.
It looks great but you should add some basic usage howto. It is obvious that you know how to use it, you created it, but other people do not.
The first time I used it it was very frustrating because I only created circle handlers, and said: This is sh*t!! Then I close the window and looked back at the sample image and saw square pointers, so I said: There must be some key that creates square pointers. After trying again I discover it creates square handlers by default.
This is the typical engineer mindset, after having spent years doing something they consider obvious what it is not.
Read "The Design of everyday things" for more design concepts if you are interested.