After my request, Ellion sent me this. It is a pity, that this doesn't work with NETwork and with directories too:
2. Favorites (menu-browser-HDD-choose your favorite contents)
You can enjoy your favorite files as the steps below.
10-1 Press GUIDE button on Remote Control or on Front key.
10-2 Select Browser by pressing ◄,► button and press ENTER button on Remote
Control or OK button on Front Key
10-3 Select HDD to make favorite files by pressing ▲,▼ button on remote control.
Favorite files can be selected only from HDD.
10-4 Press ◄, ► button to select All category where you can select AV files for favorite
10-5 Select your required file by pressing ▲,▼button and press Volume(+)
button on remote control to select the file as your favorite. Press ▲,▼ button
to select another favorite file. Press Volume(-) to load the selected files
to favorite folder.
10-6 Unload files from Favorites folder
Select the file you want to delete in the Favorite folder by pressing ▲,▼ button and
press Volume(+) button on remote control. Press ▲,▼ button and Volume (+)
to select another file. Press Volume (-) to delete the files in the Favorite
folder. You can find out the files you selected were deleted in the Favorite folder.