Thanks!
Logs investigation gives us nothing except that I've found that my kernel is newer
(kernel is not a part of KoboRoot.tgz)
Our next steps:
1. please run chess. It have timer (clock) at the top. It updates every 10 seconds. Does it also freeze or timer (clock) continue to work?
2. I've uploaded the KoboLauncherN.sh.zip. Please unzip it and replace the original file. Does Kobo Launcher freeze now? (start it from nickel).