Flash in the following manner-
1st Flash the ROM
2nd Flash GApps
3rd Flash latest SuperSU by Chainfire
Note: Use TWRP provided by Daniel to flash. All instructions are provided on the XDA forum provided above.
I have been using a Samsung Galaxy Tab 7.0 Plus for over 2 years now. Samsung had stopped updates for this tab after 4.0.4 ICS in India. Few countries got updates to 4.1.2 Jelly Bean.
I was really disappointed because even CyanogenMod didn't officially support this device. However, I found the unofficial 4.2.1 Jelly Bean ROM and I installed it. It used to lag but I was happy that I got a software update.
Recently I found an unofficial 4.4.2 KitKat ROM (Unofficial) and I said that I will flash it immediately.
I will take you through the steps that I followed. The ROM has a few bugs. The screen distorts when the screen is rotated. However, I love that I have the upgraded and latest OS on my device.
All this was provided to us by Daniel. Follow him on XDA and support him-
There are 2 major steps in flashing custom ROMs-
1. Rooting the Device-
First do Step 1
2. Flashing the Cyanogenmod unofficial 4.4.2 KitKat ROM and GApps-
Download these 2 files on the XDA developer's page and store it on the external SD card.
Reboot the device into recovery mode by holding the Volume Up button along with the Power button. As soon as you see the Samsung logo on your screen, let go of the Power button but keep the Volume Up button pressed.
Once your tablet has booted in recovery mode, click on "wipe data/factory reset" then click on "wipe cache partition" (You can use the Volume up and down button to move up and down to select options and power button to click the options)
Once you have done that click on "Install zip from SD card" and click "cm-11-20140410-UNOFFICIAL-p6200" and wait for it to complete.
Once it completes the click on "gapps-kk-20140105-signed" and wait for it to complete
Then you can click on "Reboot System Now".
Your tab should take 5-10 mins to reboot and install the ROM. In case Gapps does not work the reboot into recovery mode and only select Gapps and reboot again. It should probably work.
Caution: Do this at your own risk. The author is not responsible for your device getting bricked.