de archicad makes me confused

i just starting to learn a new softway_archicad_to draw my 3d
but a lots of problem i faced
it's very complicated
din lyk de autocad or sketch up i learned b4

i had been draw de plan in autocad
but actually it can import to archicad to continue de 3d
donno y?
i can't do tat
i asked my senior to help me
but he can't did it oso
so,i ned to redraw de plan in archicad

a lots of setting wan to control when u start to use
wall setting,column setting, door setting, window setting..
n my problem is de slab setting
i can't change de slab setting T.T

de slab i proposed in autocad is 150mm thick
but in archicad,de slab setting der is 300mm thick
de thickness of de slab is locked
i donno how to change it
i asked de help from my senior again
but he oso can't find out wat is my problem

den i try by myself,click here n der
i wish to find out so tat i can continue my work
unfortunately, i can't find it oso
my work stopped der
i can't continue my work

a frenz,bernard here oso starting it same wif me
but he doesn't has any problem wif it
he does his work smoothly,
T.T i'm late..
y? y? y?
my senior oso said, i'm so bizarre..