Video issues on install

[Bondtrails]

Hey everyone,
I just downloaded YDL v2.3 and am trying to install it on an old Umax 
S900 (with the infamous--and notorious--IMS Twin Turbo 8Meg video card).
My UmaxS900 is loaded with OS 9.1, has 160 Meg RAM, 3 SCSI hard drives, 
and 1 SCSI Jazz drive (where I wish to load YDL).

Anyway, after installing BootX, I select all the default options and 
see the usual YDL startup screen. Once the graphical installer comes 
up, my screen is compressed in half! My entire screen is squeezed in 
from the left side to the middle, and from the middle to the right side 
its all black. I can barely make out the words in the first few 
installation screens before I give up.

Anyone know what's going on? I've even gone as far as specifying the 
following kernel arguments:
video=tt128mb8:vmode:6,cmode:8
So far I have run into a brick wall.

Can someone help?

--Bondster!!