In the USB menu the red button is labeled mode. It defauts to SW upgrade but there are also S/W + User Data Upgrade, Bootloader + S/W Upgrade, Channel Data Upgrade, STB > USB: Firmware, STB > USB: Channel Data.

When you do the STB > USB: Channel Data you end up with a channelxyz.dat file. This file is not clear text though and I don't believe it is in channel master format. It would be nice to be able to manipulate the channel list off line.