Today I was able to install kitkat 4.4.4 on XPERIA L.
It took three days for installation, for installation flow to understand (I have Xepria-C2104).
[ NOTE : Try PdaNetA4150 if Xperia-L drivers not installed. ]
Step 1. Enable "Andiod Developer" and "Unknown Source" from setting.
Step 2. Download "Flashtool\FlashTool.exe".
Steps 3. Root Xepria L [ I used "Kingo Android ROOT" and done in 15 min, very easy]
At time of rooting keep also running FlashTool, so that is will install busy box etc.
Step 4. Check the android version, should be at leasr 4.2.x for wifi to work.
For Xperia L C2104 it is 4.1.x, so must download and install "C2104_15.3.A.0.26_WORLD-A.ftf"
One can use "FlashTool" to flash new Rom in flashmode.
Use FlashTool to "reboot in fastboot mode(via ADB) option.
If Step-4 is performed go through again from Step-3,4 one migrated to 4.2.x.
Step 5. Unlock Xperia L.
a). Get "Xperia L", unlock code generated from Sony Site.
b). Use FlashTool to "reboot in fastboot mode(via ADB) option.
c). From "FlashTool" toolbar, select BLU button to unlock phone.
Download "Minimal ADB and Fastboot" and use command
fastboot -i 0x0fce oem unlock 0x[your code from Sony]
d). reboot the Phone.
e). Download "cwm-xperiaL" and run install.bat from "Minimal ADB and Fastboot".
f). reboot the phone and keep tapping volume-down to check if clock mode installed.
g). Download "pa_gapps-modular-micro-4.4.4-20140716-signed" and ROM "cm-11-20140620-UNOFFICIAL-taoshan"
h). Use FlashTool to "reboot in fastboot mode(via ADB) option.
i). From commend line of, "Minimal ADB and Fastboot", copy boot.img from "cm-11-20140620-UNOFFICIAL-taoshan".zip to phone as:
fastboot flash boot boot.img
j). reboot phone in recovery by tapping volume-down button.
Now select ROM zip from SD/internal storage "cm-11-20140620-UNOFFICIAL-taoshan".zip.
Once done ...
Now select gapp zip from SD/internal storage ""pa_gapps-modular-micro-4.4.4-20140716-signed"".
h). Reboot and done :).