The first sales have come in! The marketing was basically releasing a series of videos on youtube and my blog, and then sharing them on Amiga computer forums.
I have the advantage that the Amiga computer community already know and respect me. Plus, they're always happy to see new software for their platform. So, less persuasion was required then if it had been to a cold audience. On the downside, the Amiga computer community is also small, so I'll hit saturation quickly.
The first bug reports have also come in, and I have a lot of features that need to be implemented before I'm confident enough to release the Windows version. There's lot's of work to do...