Set current camera doesn't work.
sync on
sync rate 60
color backdrop 0,0
make camera 1 : color backdrop 1,rgb(255,0,0)
set current camera 0
make object cube 1,10
do
text 0,0,"black background : cam #0, red background : cam #1"
sync
loop
"When more than one camera exists, and a camera
command is used without specifying a camera number, the active camera is used"
sync on
sync rate 60
make camera 1
make camera 2
make object cube 1,10
position camera 0,0,0,0
position camera 1,-100,-100,-100
position camera 2,-200,200,100
set current camera 2
do
text 0,0,"cam #2 pos : -200;200;100"
text 0,20,"real pos : "+str$(camera position x())+";"+str$(camera position y())+";"+str$(camera position z())
sync
loop