@Pepar I just went through this process. I installed it and added it to wifi, was able to access it from my router, but keep in mind the IP address changes when connected to wifi versus when connected to directly to the device. I had to go on my router to get the actual IP address of the device to be able to hit it from my web browser. That said, there's not much you can do over normal wifi, it requires you to do everything connected directly.
Mine had an old firmware, so I downloaded the firmware on my phone from
this page, then connected directly to the connector (by holding down the button on the handle for 5 or so seconds so it started the onboard wifi back up) and connecting to the WallConnector SSID. I then went to
http://192.168.92.1/update and uploaded the firmware i had downloaded on my phone then hit upload. It then took me to
http://192.168.92.1/fwupdate where it said I had new firmware available and told me to click to update. I did that, after a few minutes it rebooted, and I'm now on the new version. I had to reconfigure the amps (it asks you what region you're in) and something else I don't remember, but now all is good.
Interestingly the new version doesn't have a status page available from your normal wifi, you have to connect directly to see anything. It also now has an option that lets you choose whether non-teslas can connect or only teslas.