Installation on LPT100F based Smart Plug

[GitOeli]

Hello,
I've been trying to install this on a LPT100F based SmartPlug, but either I'm doing something wrong or something isn't working as intended. First way I tried was using the webinterface by connecting to the IP of the device and going to Upgrade SW. I entered HFEASY_WEB_UPGRADE.bin file, hit upload and after a progress bar it showed the ip of the switch has send no data. Refreshing the page get's me back to the default web interface. I tried several browsers (including Chrome) and several PCs Afterwards I tried putting /iweb.html behind the IP. There I've got the option to update the application as well as the webpage. I've tried HFEASY_WEB_UPGRADE.bin as the application, but after doing so I'm just back at the default webpage. /state and /config just get me a 404 Error I also tried using it as an update for the webpage but that only gets me a 404 error on the device IP.
Before I'm heading down the serial route, is there something I'm doing wrong here? I couldn't find any instructions for installations so I assume this must be quite easy and I'm either doing something simple wrong or something isn't working.