Help needed, why does on/off switch show big buttons instead of a small switch

I published a plugin on the forum and people started to complain because they couldn’t
find the controls on the “control” screen.
The reason : at my side there’s a small “sliderswitch” (on/off) in combination with a
“brightnessslider”.
At their side BIG on/off (square) buttons are showing uo and they pusch all the other controls from the screen.
How can this happen, and how can I let Vera choose the litle “sliderswitch” ?

Thanks in advance,