Alright, I finally got the drivers properly installed (also to work in Download Mode) and found proper Bootloader/PDA/CSC files (i9023EUR) for Odin and managed to do the flash update (however Odin I used is called I9003_Odin3 v1.82, don't know if that is a problem).
Then I should do a factory wipe, which works (Bootloader -> Recovery -> Wipe), but if I explore the phone I can see that all data is still present (all images, music, etc). So the hard drive still seems fixed.
I found out that I did not post my last update. I managed to flash with Odin, and I can get into the Bootloader menu to wipe the phone's data. I can, in Recovery Mode, also see the hard drive and it seems to be empty. That is, the phone fails to see it.
When I reboot out of Recovery Mode the phone gets stuck at the Google logo and that's it..
Flashing Clockwork did work, but if I understand correctly I have to copy the stock rom to the phone and load it in Recovery Mode? When I connect the phone to my PC it is recognized as an Android Phone (and even as a Nexus S) but the drive it shows up as seems to be recognized as empty ("Please insert a disk into Removable Disk (E.").
So what do I do?
What is sort of promising is that it indeed was capable to flash Clockwork. So the memory is not completely stuck. However, when I do a format, still nothing happens (phone isn't formatted).
Update: I am able to mount the phone to USB and I can access the phone via Windows. However, I can still not format the SD Card (which is of course internal) or put files (stock rom) on it. Are there other tricks to flash a stock rom? If not, it does indeed seem to be that I cannot flash a custom/stock rom because the drive of the Nexus is frozen/broken/whatever.
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