I contacted the dev some months ago, he said that support for WebOS 2.0 wouldn't happen but that he would possibly fix the issue on WebOS 3.0. But this was a while ago and he already updated the app without fixing it so dunno if it will happen or not.
Not sure which LG are you using but on my and many others it doesn't work, you can only active them (being the first one used) but not select other languages. The actual dev acknowledged this and said was going to push and update to fix this.
1. Are you using an ethernet cable to connect your smart tv? If yes, are you using any kind of switch between your tv and router?
2. Have you tried resetting/rebooting your router?
3. Have you tried changing dns server on your tv to 8.8.8.8?