Self boot toolkit not working

i downloaded Selfboot Toolkit 3.5 and it works up to one point. When i have to make a iso using mkisofs.exe. Its down hill from there. It doesn't make a iso or sometimes it does but the iso is 32k and when i burn it nothing happens.

Can anyone tell me why its not working

[xena]

make sure
all game data in dir c:\selfboot\data
"ip.bin" & "bootbin" in dir c:\selfboot\data
hv enough free hd space to build iso