Finally, the complete cheat for Guru Logic MSX2 version !
It was not evident to find the cheats for selecting the level, I had to use both the blueMSX debugger and WinHex !!!
!cheats for blueMSX :guru logic msx2
!(c) 2006 Benoît Delvaux
0,42636,17,0,infinite time
0,39877,0,0,level (0-4)
0,52224,0,0,level (0-4)
Addresses for openMSX : A68C, 9BC5, CC00