MkIII blank screen after dead battery change

[PhinHead]

I know this has been covered, and I have read countless threads on Nav losing OS because of changing the battery. I also know that since I have a MKIII nav, that any version beyond v23 is all identical as far as use in my MKIII. But I have been unsuccessful in getting the nav to boot off of any of my created CDs. I think it could be the initial cheap CDs I used, so I bought some Sony ones, maybe I'll buy some Memorex ones today. But 1 thing I noticed is that I have seen 3 different file types that get written to the CD, depending on where I down loaded the os software from. 1st download (v27) has as its main file "bmw v27.mdf", 2nd download (v23) was a cloned CD image and its main file is "BMW_v23_update_darci.ccd", and the 3rd download (v31) has its main file as "v31_OEM.bin". I have always used winrar to extract the files and alcohol120 to burn them on to various CDs.

I have followed the steps of putting key in position #1, I wait 5 minutes (since my screen is blank I can't see when the nav has booted) and then I insert the burned CD into the nav unit in trunk. I never have seen anything come up on my screen other than some white junk flashes that come up regardless if I have a CD inserted in the unit, only LED that comes on on the nav unit is the eject LED, never the "power" LED.

I am desperately trying to NOT buy a new nav unit, also my radio only stays on for 2min40sec then cuts out, which I was told MIGHT be that the bmw iBus senses a problem with a device on the bus and therefore shuts the bus traffic down, hence the radio cuts out.

I bet all this sounds familiar. My last download, was extracted but when I went to burn it using alcohol120, it wouldn't burn, so I will try to download another version and burn it to a new CD. Any pointers, like where is the BEST download version to get the OS from. Second, how do I know the difference between Mode 2 and Mode 1 and what is the harm if by chance one of the OS CDs I burned and tried was a Mode 1 and I am in US.

Thats enough questions for now.