Actually you can. Look into the disable object zread command. Though it is picky and not exactly the best way to do it ... it does work until they give us something better. Just remember that the disable object zread gives priority by image numbers. The objects you want drawn behind others need to have the lowest image numbers.
[edit] for better example code. Hold the spacekey to make the plain draw like a normal object. With the spacekey not held it is drawn behind the sphere.
`make textures so you don't need any media
create bitmap 1,screen width(),screen height()
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
print "Testing Draw To Back : Testing Draw To Back : Testing Draw To Back"
get image 1,0,0,screen width(),screen height()
cls
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
print "Object : Object : Object : Object : Object : Object : Object"
get image 2,0,0,screen width()/2,screen height()/2
cls
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
print "Testing Draw To Front : Testing Draw To Front : Testing Draw To Front : Testing Draw To Front"
get image 3,0,0,screen width()/2,screen height()/5
cls
delete bitmap 1
set current bitmap 0
`Here is actual code
sync on: sync rate 60
autocam off
color backdrop 0
position camera 0,0,-7.7
`make plain to use for drawing to the back
make object plain 1,12,8
texture object 1, 1
set object transparency 1,1
`make object for middle drawing
make object sphere 2,5
texture object 2, 2
position object 2,0,0,5
`use sprite to draw in front
sprite 3,screen width()/3,screen height()/3,3
direction = 1
do
if direction = 1
position object 2,0,0,object position z(2) + .05
if object position z(2) >= 7
direction = 0
endif
endif
if direction = 0
position object 2,0,0,object position z(2) - .05
if object position z(2) <= -2
direction = 1
endif
endif
if spacekey() = 0
disable object zread 1
else
enable object zread 1
endif
set cursor 5,5
print object position z(2)
set cursor 5,20
if object position z(2) >= 3
print "Sphere is behind plain"
endif
if object position z(2) <= 1
print "Sphere is in front of plain"
endif
sync
loop
