Install custom recovery & custom rom 100 per tested work personally, now we came up with another tested work of mine upgrade s1 from CWR without problems one thing i wana tall you before the procedure is that this model is korean shw m110i people say it cant be flash but i say it can be done easily you can flash any custom rom move to process
first of all download drivers to pc and install them. then download the odin.
put you phone in download mode menu softkey & power button at same time easy way press menu and home button and then press power
in other models just home button and power so try your self
next open odin it will detect your phone in yellow box
As seen in pic at com 15 dont scared if port is changed you phone detection is main purpose
download CWR image file, in odin just check auto reboot & reset time unchecked all other option of simply leave it empty , next click PDA and locate the image file that download.
just click start and be patient dont touch anything it ill brick the phone leave it till it says done flash factory etc aftet that phone will reboot into recovery auto, now simply wipe data factory cache and flash from sd card locate your rom its done rebot and enjoy download proper rom coz in some roms network or baseband seems empty and sim wont work ill find its solution later and post it here one rom .
WE ARE NOT RESPONSIBLE OF ANY DAMAGE SIMPLE PROCEDURE NO STORY AT ALL
GOOD LUCK
Download Drivers
Download Odin
Download CWR
Download ROM