When your wallet is opened (assuming you have set up the .conf file as explained above), it is opening as a node - there is no additional step needed to make it a node that's able to link up with other wallets.

Try opening the wallet on two computers in the same network, and using addnode to point each one to the other's internal IP address (no port number needed). If this works, then your issue is network/firewall/port related, not a problem with the wallets/nodes themselves. Firewalls and port forwarding can be tricky depending on your network configuration, but is more general IT than an altcoin config issue.