You are 100% sure the dish is tuned and plugged in correctly to the receiver?
Since you cannot get any networking to work and no signal to work it may be the box is totally faulty. That would be rare so maybe you are trying to do too much in one go and need to start right from scratch, one step at a time. Back to basics.
Right, if you know that the dish is tuned and working, make sure cable connections are correct and make sure the co-ax is going into the correct input on the rear of the receiver.
You need to use a null-modem serial lead to load the original firmware on the receiver. Get the software from the official dreambox site, you need 'Dreamup' for the loader and then the released firmware for your box.
Once you have the box totally back to brand-new then use the original manual that comes with the receiver. You should then be able to set up a standard working sat system- Dish > co-ax > box > tv
Once you have that working as per the manual you can then move on to upgrading, no offence intended but its the only suggestion I have left.
Report back which step you get stuck at.