"Compare your block and item IDs from server to client; there's probably a mismatch."
I doubt its a block ID Conflict as My Dev server is ONLY running IC2. The Block ID Conflicts are all resolved on my Live Server.
I should read more thoroughly, The server and client on my dev server are using the same config file, I make it a point to copy over the client configs so they match, unless the config file is different in someway of course