Unfortunately, the game is developed in Multimedia Fusion 2 where controller support, though supported through a third party extension, is a bit awkward to add. On top of that, the game uses a custom exporter where it have to be re-implemented for three platforms. I'm fully aware that it would have been very nice to have controller support. Luckily, things will be a lot easier in the future since I've switched to Unity where everything just works for every desktop platform right away. This is basically why none of my pre-Unity games have had controller support, while all my Unity ones (well, only two mini games for now) has it.
I do agree it is dodgy to have to rely on external software for controller support. Sorry about that.