Create a folder rossi2000 in your OE recipes folder and clone the repo inside

mkdir /your/oe/path/recipes/rossi2000
cd /your/oe/path/recipes/rossi2000
git clone git://github.com/rossi2000/rossi2000.git .

Edit the file "/your/oe/path/recipes/images/dreambox-image.bb"
Change OPENDREAMBOX_COMMON from:

OPENDREAMBOX_COMMON = "\
	task-boot \
	task-opendreambox-base \
	task-opendreambox-dvbapi \
	task-opendreambox-ui \
"

to:

OPENDREAMBOX_COMMON = "\
	task-boot \
	task-opendreambox-base \
	task-opendreambox-dvbapi \
	task-opendreambox-ui \
	task-rossi2000 \
"

Compile your OE :)