Documentation
The interraction between the application and the DMX controller is described by the following figure. It's basically the same than the one used by the official (Windows) driver.
The USB protocol is very simple and is described in the USB Protocol documentation. It has been extracted from the driver source, not from the PIC source. Other commands may exist but are unused by Velleman
The protocol used between client and daemon is described in the Daemon Communication Documentation. Please note that this protocol will change in the future as new features will be added.
The helper object (will change to a library at a later time) is described in the Helper documentation page.
Please keep in mind that it's still a work in progress and that you should check the documentation if you intend to use this in your own projects