Today i flash unlock and downgrade u880 without box.
here is detail,
1st run Setup.exe to install the Windows USB driver for LG U880 if you haven't install
now run LGMDP_H3G.exe and select comport.
connect ur phone with usb cable by pressing 2+5
erase ur phone and wait for a moment to reconnect ur mobile
again click select comport and give the following files
U880-CODE-downgrade_v11@v10bwm_by jarabe83.BIN { as a amss modem and for downgrade}
U880-MEDIA-V10b_wm-FEB-08-2006-H3G-UK.bin [ media file]
U880-MODULE-V10b_final_unlock_kller_4_all_unlock[ module for unlocking]
click start and don't disconnect usb untill it show download complete. it proceed automatically
here is all files and setup