I use static IP between the Amiga and PC. Ensure that the Subnet Mask is consistent between all the connected network equipment and the Gateway IP is consistent.
Also ensure that the IP addresses use the same format on each computer. Enter the IPs / Computer names in to the hosts section on Genesis or Miami.
Also ensure the Workgroup name is consistent between every computer and Windows XP accepts shared access on the folder you want to share on the network
Example:
DSL Router
----------
IP address: 192.168.0.1
Subnet Mask 255.255.255.0
PC
--
IP address: 192.168.0.2
Gateway: 192.168.0.1
Subnet Mask 255.255.255.0
Amiga
-----
IP address: 192.168.0.3
Gateway: 192.168.0.1
Subnet Mask 255.255.255.0
