Hi Linas,
by the first, sry my bad english.
I have had the same problem with an old Sony Vaio PCG N505X who has only a cd-rom over pcmcia.
The resolve was:
Burn the cd a second time, take it in an seperate cd-rom-drive at the usb-port.
Then start the installation again with reboot.
He find the other cd-rom and i can take my network-card inside the pcmcia port.
So it works.
I hope that helps you also,
Regards,
Cleanersworld