[Drax]

the rhino should be fine if you place it behind scenery for deployment, move it as far as possible and pop the smokes, then move again disembark and let rip with bolters.

with the mark of Tzeentch, as has been stated, you may take and use two powers per turn, the only exception to this is that you cannot use two shooting powers per turn, so warptime could be a useful second power.

as for the force weapon, that is where it gets tricky. their rules state that if you use a psychic power in your turn, you cannot use the force weapon in the combat phase. presumably when the rules were written for it, they were working on the basis that psykers were limited to one power anyway. however, the Tzeentch rules state that they may use two powers per turn, so until an faq is released, or unless there is something in the 5th ed wording, then it is unclear if the intention of the Tzeentch wording is intended to allow the force weapon to be used as well.

another problem with the Tzeentch wording is that it clearly states that a model my not use two powers that count as shooting, on the basis that the vast majority of models may only shoot once, Monstrous creatures (i.e. Daemon Princes) may shoot twice - so in this case, the Tzeentch wording denies them the bones that the monstrous creature wording grants them!

then of course there is the MoT on a turbo boosting bike arguement...