I tried the games with the joystick - it works if I use the "a" key as fire. Then I can use the joystick to move around. However, the fire button on the joystick does not work, I still need to use "a" to fire.
In the source I see that the joystick fire button is not used. In the joystick configuration used (which is PET dual joysticks), fire means up and down pressed at the same time - i.e. bits 0 and 1 cleared on the userport at the same time.
It would be awesome if you could add that!