i started with right crossover and yeh tatw was harder to learn but not impossible..
the key is to start the tatw low.
do an atw low to the ground, when u get 3/4 round the ball , try to flick it up with ur big toe.
if ur have trouble getting ur left foot over the ball, it means ur probs not hitting it high enuf or ur timing ur tatw wrong.
i think the easiest way is to do it from a standard flick up at first because u have greater control over the ball.
its harder from footstall because with footstall, when you do the atw part, the ball goes relatively high and that is dangerous for tatw as the chances of stacking increase
once u get it, it'll become easy

..but keep practicing and my suggestion is work on ur timing...try to watch vids where ppl show tatw close up (hard to find i know..lol) and see how they do it ;)