You *DON'T NEED* to transfer anything to the Client PC for it to use the ICS connection. Simply connect it to the Host PC, either by crossover ethernet cable or with an Ad Hoc wireless network, and ensure that its network adapter is set to get its IP and DNS Server addresses automatically.
When you enable ICS on the actual internet connection (modem connection) in the Host PC, Windows will allocate the IP address 192.168.0.1 to the network adapter with which you're connecting to the Client PC. The Client then gets its addresses by DHCP from the Host PC.
Because ICS uses the 192.168.0.0 Subnet (i.e. the Host PC's adapter has the address 192.168.0.1 and the Client gets an address between 192.168.0.2 and 192.168.0.254) it is important that, if you're using a Router, it doesn't also operate in this Subnet (IP address range). As you are using ICS though, presumably there isn't a router involved and you have a USB ADSL Modem?