I have done pretty much everything in the game myself, got pretty much all the "special" characters, well it may not be a trick to get Cloud but you must do certain things to get the sequence where pops out of the machine.
The way to level up Cloud is to get him hit one of your own higher levels so he gain a lot more Exp, it will speed up the process - but yes it is time consuming and I have not unlocked every move on his Limit skill.
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