solved it.
https://www2.mobileread.com/i/smiliesadd1/thumbsup.gif. what have I done:
1. formated again the mSD -- (in Debian with parted -- from my perspective shouldn't matter the tool, but it was the only 1 which did the job[tried gparted, fdisk, gnu-fdisk])
2. put the device in sleep mode
3. shut down completely (reset+shutdown buttons)
4. inserted the mSD with the "OS Firmware" (copied again on the new formatted FAT32)
5. followed instructions -- pressed Home+Menu until the end of the loading process, then released
6. the blinking started and w8ed for about 20 min (as I was away for some minutes didnt noticed what happened, but the loading bar wasnt full anymore. I've waited for some more minutes and decided to remove de the mSD and restart/initialize the device)
7. everything looks ok now -- opened a book and scrolled a few pages.
1 more thing -- shall I root the device again (are there some critical points in the tutorial which should I be aware of?)?. I think the instruction are simple and clear, dunno what I've missed.
https://www2.mobileread.com/i/smiliestext/thankyou.gif vishcompany