Here is the version 1.3.1, that includes a stability bugfix (for Windows) and a big personal fulfillment: a native Linux VST version. Following what I did in the Windows version, the Linux version was made without frameworks, using the Xlib directly. The code of both versions are very didatic, following the same structure and is a good start point for who want to learn how to do the same. The binaries (Windows and Linux, 32 and 64-bit) are available here.
on Qtractor (using a non-default skin):
Thank Dave Phillips and Rui Nuno Capela by the tests on Linux, Doktor Italics, Layzer and Phil Considine for tests on Windows.