Parition Problem on G3 Installtion

[Stephen Ko]

Hello,

I've spent several hours trying to install 4.0 on G3 but failed due to
partition problem. When I tried to partition 200GB, for some reason,
YDL reserves almost all the space to apple partition map(I think it
was around 190 GB) which only leaves me with 10 GB to play around
with. Neither the autopartition nor the disk druid seems to do the
trick. So I am pretty much stuck with 10 GB which apple bootstrap,
swap, and / must share.

Can anyone please tell me what I am doing wrong?

Thank you,
Stephen.