I have put about 300 books in main memory on 3 subdirs, 5 additional fonts, about 600 books on SD, 6 subdirs. This morning my device still slow respons on my touch or power slide, the blue LED always light on. After 3 minutes, I charge and slide the power switch many times and at last reboot.
Now I try to reinitialize and watch after that.
Thank you AlPe for the response.