Reevan, please do not go into other threads and ask people to look at your thread, it's basically spam.
Unless it explicitly says otherwise (like in the SM codex), if a transport is offered you may take it regardless of the unit's size. However, if the unit is too big to fit inside you may not ride inside it unl;ess you have the ability to break up the unit (like Combat Squads)
Dark and Blood Angels can take a Razorback with a 10 man squad, they just can't ride inside it unless they split the squad first.
Large CSM squads may have a rhino, but they cannot ride in it until enough of their unit has been killed off to allow them to fit inside (since chaos does not have a combat squad option)