Yes it is possible. DarkAI Only use's the X and Z Coordinates to control characters, which is all thats needed, the Y coordinates of your object is up to you. If you want it to walk on top of a terrain, that is an .x file. Use this.
`Players coords
objectx#=object position x(playerobj)
objecty#=object position y(playerobj)
objectz#=object position z(playerobj)
`intersect used to tell Y of Terrain
distance# = intersect object( TerrainObjnum, objectX#, objectY#, objectz#, objectX#, -40, objectZ# )
groundHeight# = objectY# - distance#
`Position player with new coords.
position object playerobj,object position x(playerobj),groundheight#,object position z(playerobj)
Hope that helps even though that is for DBpro and you are using DarkGDK.