Instructions for English/QWERTY people who want to play:
1) Press CTRL+Y to bring up the control config
2) Click the empty "Clavier" box in the 1st column to switch to keyboard controls and bring up the keyboard config
3) The first column is Up, Down, Left, Right and the second column is Shoot, Aim, and probably Select/Start or Start/Select
4) To get the Joystick working I had to click on Joystick 2 instead of Joystick 1 in the 1st column and it uses the Analog stick (the D-Pad isn't supported even on menus) and A as Shoot, B as Aim (X-Box One controller)
5) I had a ton of trouble actually playing it until I found the best way and then it became really fun: hold down the Shoot button and whenever you want to switch directions just move the analog toward the new way you want to shoot and just TAP the Aim button...this keeps you the most agile while allowing you to aim wherever you want!
Once you get the controls set up and play it the way I described (and how the developer probably intended for people to play it) it's actually really fun to play! I wanted to share these instructions just so no one misses out on trying this 'cause it's a really cool game! :)