Hi,
Did you solve your issue ?
You are probably setting up your controller in Teknoparrot while your Sinden is pointing away. In this case the key mapping is different and most keys are binded to MouseRight by default.
You can fix this by setting up the controller in Tecknoparrot with the gun itself or by mapping different "pointing away" keys in the Lightgun.exe utility.
Let me know if it helped.
(just got my guns and was running into the same issue, that's how I found your post)