Xbox Black Screens When I Upload A New KV

I got a new KV today, but when I try to flash it (I've used J-Runner, and Flash360) it causes my Xbox to Black Screen with on the middle light on the Power Button lighting up. It stays like this until I flash my stock NAND through Xell.

Any help?

Spoiler

Spoiler

 

Best off just putting the KV on the root of your hdd, saves time

 

I'd do that, but I've seen stories of Stealth Servers stealing your KVs to sell as Shared. Don't know if they're true or not, but I really don't want to take the chance!

 

Is the KV type 1 / type 2 (slim) - I will be making a tut upon how to "properly" flash your KV to the nand.