Yes I put the phone into Recovery Mode. I wipe cache before and after flashing the new custom rom. But I'm not sure I did the data/factory after installing.
I'll try that when I'm home from work.

I thought the bootloader was part of the official samsung firmware (nordic version), which I installed first. And then later I installed the custom firmware.
both the official firmware and custom firmware/rom wont go past the boot animation (the one with sound and colors flying around).
Could it be that the offset for the bootloader or data partion isn't correct somehow ? I would just imagine that the bootloader is at the same location of all the versions/editions of the firmware. And the rest is just more about partition size then location... (order of the partitions are properly also important)