here's a basic movement that might help. It doesn't make the object rotate, but you can use the "rotate object obj,x,y,z" command for that. This uses advanced terrain (object 3), (player is obj 1), but you can substitute your "y" position for ground#, if you're not using advanced terrain.
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speed#=4
`Control Player with the cursor keys
if upkey()=1
posx#=newxvalue(posx#, angle#, speed#)
posz#=newzvalue(posz#, angle#, speed#)
endif
if downkey()=1
posx#=newxvalue(posx#, angle#, 0-speed#)
posz#=newzvalue(posz#, angle#, 0-speed#)
endif
if leftkey()=1 then angle#=wrapvalue(angle#-speed#)
if rightkey()=1 then angle#=wrapvalue(angle#+speed#)
ground#=get terrain ground height(3,posx#,posz#)
position object 1,posx#,ground#,posz#