few tips :
at first like at the drawing lessons try to draw with your arm and not the wrist.
one great thing to practice your ability is to play those web games like pop-up and tetris with the tablet.
about the inking\weight thing...there is an option in the tablet preferences that let's you test and decide how much pressure you want to use , in painter and photoshop the inking should work , try to re-install the drivers.
one little trivial thing , don't work too close too the screen with the tablet board, it tends to create shekes that will creep you out about the "crap" tablet you bought. also don't position yourself too close since it narrows your view .