I just wanted to share some experiences. I have had a Devo 7e with a blue/blank screen for quite some time. I modified my 7e with Deviation of course and then put in a NRF24L01 module and never could get it to recognize the module. I soldered and resoldered. Finally I removed everything I did and rebooted. Got a blank/blue screen. I tried everything from a software perspective and nothing worked (even going back to original). Finally got in a new NRF24L01 and put the new one in. Blue screen magically went away and now everything works. Bottom line - It was a hardware problem the whole time. My redoing the connections all over again fixed the problem
If you have a blue/blank screen and have reloaded Deviation and file system - don't do what I did for weeks. It is a hardware problem and you need to fix that before proceeding. If you haven't loaded the file system with the USB connection, there are plenty of videos that instruct you on how to do that. If you do that multiple times (reformatting after each dfu load) and it still doesn't solve the problem, you have a hardware (soldering) problem.
Just didn't want anyone going through what I just did to get this working again.