When using this version of the software you should not register the gateway with EUI (legacy mode), you should use a ‘human readable’ name.
Create a new gateway on TTN, do NOT check the ‘Legacy’ checkbox, choose a nice name, set all other settings to the correct values.
The re-run the installer telling it you need to reconfigure.
After the software started it should be forwarding data to TTN. The last few lines of output from the installer tell you where to check if things run correctly on the gateway. (tail …)
Oh, and keep in mind TTN does not store gateway traffic. Only packets arriving while you are looking at the traffic page will be shown, no historic data.