Create a cube normally,choose explode in objects menu.
Let the 1.0 in the requester "Detonate"
now select each side and give them step by step a texture (exactly 6)
Then choose explode again but change the 1.0 to -1.0 and the cube is united with a texture each side.
This is an example only.
Peter
PS for the cylinder iŽll maka a next step.