Hello No, there are no losses. Simply connect the Arc to the HDMI eArc port and set it to passthroug in the audio menu on the TV.

Good evening, no idea.

Yes everything fine

Hello, they are 2.0a HDMI outputs. Greetings

In my opinion, this should work, but I haven't tried it from a CD yet either. I can play UHD videos via the USB connection from an external HD. Ultimately, it depends on the format of the video file. The relevant information should be apparent from the data sheet.

Apart from my stereo and radio, I have transferred all my remote controls to my Harmony 650 universal control. Even my ancient ODYS kitchen TV, 15", runs via this remote control. Maybe as an alternative to the general remote control chaos? Otherwise, I'm afraid I can't say anything about it. I'm sorry. Lately, only the most necessary buttons are attached to the devices, sometimes not even those. :-(

Yes, that is possible.

Yes, that is possible. Enclosed are the instructions: https://www.lg.com/de/support/service-produkt/lg-UBK90

No.