[LG Optimus L9 P760, P765, P768, P769] ncerni:
I flashed stuff like you said, and I took u-boot.bin for ICS P760 from this thread: http://xdaforums.com/showthread.php?t=2292828

When I connect the phone to AC charger it says: S/W update - same as before.

But now I tried offline KDZ flashing, without compatibility mode, and I got a little bit further. Here is the log, but some lines may be changed, sorry.

18:06:50 : [C:\LGMobileUpgrade] Try to delete folder
18:06:50 : RemoveDirectory1 Error(2):C:\LGMobileUpgrade
18:06:50 : Start Date : 2013-05-27 18:06:50
18:06:50 : ---------- QM Testmode ---------
18:06:50 : ***** Check Tool Version *****
18:06:50 : Tool version : 1.5.4.8
18:06:50 : UpgradeDLL version : 1.2.6.7
18:06:50 : Current Dir : C:\ProgramData\LGMOBILEAX\B2C_Client
18:06:50 : LGE USB Driver Version :
18:06:50 : Android PDLV Version :
18:06:50 : Android NDLV Version :
18:06:50 : ******************************************
18:06:50 : [C:\ProgramData\LGMOBILEAX\Phone] Try to delete folder
18:06:50 : SetEmerModeAT()
18:06:50 : _IsConnectedPhone Call
18:07:12 : _IsConnectedPhone(2) <<<<< connection working somehow
18:07:12 : 0 - NotConnected.
18:07:12 : 1 - Normal connect success
18:07:12 : 2 - Emergency connect success
18:07:12 : *****CheckOS Start********
18:07:12 : Microsoft_Windows7_Professional_Service Pack 1
18:07:12 : *****CheckPCSyncPrograms Start*****
18:07:12 : PCSyncPrograms Not Found - OK and ready to upgrade
18:07:12 : Checking the connection with the cell phone...
18:07:12 : dwWaitResetTime(40000 ms)
18:07:13 : Phone Mode(2)
18:07:13 : *****GetPhoneType Start*****
18:07:13 : Phone Type : OMAP_IFX
18:07:13 : *****GetPhoneBinaryVersion Start*****
18:07:14 : *****Get ESN / IMEI / MEID Start*****
18:07:14 : ESN/IMEI/MEID : 35********30964 <<<< I got IMEI this time
18:07:14 : Phone type Compare start
18:07:14 : *****CheckPCSyncPrograms Start*****
18:07:14 : PCSyncPrograms Not Found - OK and ready to upgrade
18:07:15 : ****************CheckAndDownload********************
18:07:15 : ******Extract Start C:\Users\Nejc\Downloads\Desktop\v20c_00.kdz*****
18:07:15 : Model Dll Dir(C:\ProgramData\LGMOBILEAX\Phone\)
18:07:15 : File Size = 602780166
18:07:33 : Extract kdz file Success.
18:07:44 : Extracted C:\ProgramData\LGMOBILEAX\Phone\\V20C.wdb\n
18:07:44 : WDB(or DZ) FullPath(C:\ProgramData\LGMOBILEAX\Phone\\V20C.wdb)
18:07:45 : Extracted C:\ProgramData\LGMOBILEAX\Phone\\LGP760.dll\n
18:07:45 : Model dll FullPath(C:\ProgramData\LGMOBILEAX\Phone\\LGP760.dll)
18:07:45 : NNNNN WDB FullPath(C:\ProgramData\LGMOBILEAX\Phone\V20C.wdb)
18:07:45 : NNNNN Model dll FullPath(C:\ProgramData\LGMOBILEAX\Phone\LGP760.dll)
18:07:45 : Extract End C:\Users\Nejc\Downloads\Desktop\v20c_00.cab
18:07:45 : ------------------Model.dll Information-------------------
18:07:45 : Filename : LGP760.dll
18:07:45 : Version : 0.0.7.0
18:07:45 : File size : 290816
18:07:45 : File date : 2013/03/25-15:56:00
18:07:45 : PC Created date: 2013/05/27-18:07:44
18:07:45 : ----------------------------------------------------------
18:07:45 : *****Check LGCM Programs Start*****
18:07:45 : LGCM Programs Not Found - OK and ready to upgrade
18:07:45 : *****WorkModelDLL Start*****
18:07:45 : strPhoneBinaryPath(C:\ProgramData\LGMOBILEAX\Phone\V20C.wdb)
18:07:45 : strModuleDir(C:\ProgramData\LGMOBILEAX\Phone\)
18:07:45 : strModelDLLPath(C:\ProgramData\LGMOBILEAX\Phone\LGP760.dll)
18:07:45 : _DetachDLL Call
18:07:45 : _DetachDLL Call End
18:07:45 : Call fn_StartUpgrade
18:07:45 : ********* 2Chip Model.dll input Parameter*************
18:07:45 : MODEL_EVENT : 32769
18:07:45 : PhoneBinaryPath : C:\ProgramData\LGMOBILEAX\Phone\V20C.wdb
18:07:45 : ModuleDir : C:\ProgramData\LGMOBILEAX\Phone\
18:07:45 : BootWaitTime : 49500
18:07:45 : UsbHighSpeed : FALSE18:08:41 : wParam : 2004, lParam = 7
18:08:41 : Step : TYPE_WPARAM_IFX_DN_POS
18:08:41 : wParam : 2007, lParam = 0
18:08:41 : Step : TYPE_WPARAM_READ_FILES
18:08:41 : wParam : 2010, lParam = 3002
18:08:41 : CleanModelDll() : Free Model.dll
18:08:41 : _DetachDLL Call
18:08:41 : _DetachDLL Call End
18:08:41 : Page_Error şÎşĐŔÔ´Ď´Ů
18:08:41 : ż©±â´Â Retry şÎşĐŔÔ´Ď´Ů

18:07:45 : PhoneMode : 2
18:07:45 : NewPhoneBinVersion : v20c_00
18:07:45 : ClearSI : FALSE
18:07:45 : AuthMark : 0
18:07:45 : ********* 2Chip Model.dll input Parameter End*************
18:17:04 : Call Retry Thread
18:17:04 : Checking the connection with the cell phone...
18:17:04 : Checking the connection with the cell phone...
18:17:04 : dwWaitResetTime(40000 ms)
18:17:08 : _IsConnectedPhone Call
18:17:26 : _IsConnectedPhone(1) <<<<< connection somehow works
18:17:26 : 0 - NotConnected.
18:17:26 : 1 - Normal connect success
18:17:26 : 2 - Emergency connect success
18:17:26 : Phone Mode(1)
18:17:26 : *****WorkModelDLL Start*****
18:17:26 : _DetachDLL Call
18:17:26 : _DetachDLL Call End
18:17:26 : strPhoneBinaryPath(C:\ProgramData\LGMOBILEAX\Phone\V20C.wdb)
18:17:26 : strModuleDir(C:\ProgramData\LGMOBILEAX\Phone\)
18:17:26 : strModelDLLPath(C:\ProgramData\LGMOBILEAX\Phone\LGP760.dll)
18:17:26 : _DetachDLL Call
18:17:26 : _DetachDLL Call End
18:17:26 : Call fn_StartUpgrade
18:17:26 : ********* 2Chip Model.dll input Parameter*************
18:17:26 : MODEL_EVENT : 32769
18:17:26 : PhoneBinaryPath : C:\ProgramData\LGMOBILEAX\Phone\V20C.wdb
18:17:26 : ModuleDir : C:\ProgramData\LGMOBILEAX\Phone\
18:17:26 : BootWaitTime : 74250
18:17:26 : UsbHighSpeed : FALSE
18:17:26 : PhoneMode : 1
18:17:26 : NewPhoneBinVersion : v20c_00
18:17:26 : ClearSI : FALSE
18:17:26 : AuthMark : 0
18:17:26 : ********* 2Chip Model.dll input Parameter End*************
18:17:36 : wParam : 2004, lParam = 5
18:17:36 : Step : TYPE_WPARAM_IFX_DN_POS

18:17:56 : wParam : 2004, lParam = 6
18:18:01 : wParam : 2004, lParam = 7
18:18:01 : wParam : 2007, lParam = 0
18:18:01 : Step : TYPE_WPARAM_READ_FILES
18:18:01 : wParam : 2010, lParam = 3002
18:18:01 : CleanModelDll() : Free Model.dll
18:18:01 : _DetachDLL Call
18:18:01 : _DetachDLL Call End
18:18:01 : Page_Error şÎşĐŔÔ´Ď´Ů
18:18:01 : ż©±â´Â Retry şÎşĐŔÔ´Ď´Ů