Lesson Learned : Downgrading is ALWAYS risky, unless more than 2 people with the same device confirmed to be successful.
First of all I wanted to thank you, because I've updated to 4.4.2 and it work perfectly now. I've also sim unlocked and today I stuck in the att sim card and it seems everything's working. I was just wondering the telephone now is always say 3G signal, it means it never goes on H or H+? is that normal?
Have a look in Settings > Status, and note what is listed under mobile network type. If it says HSPA/HSPA+, all is well. Not sure why it isn't showing the H. Although I am the original developer of the Sim-Crack, I don't have an XT1056 myself - I did it for the community. Therefore I can't really tell you why it wouldn't show H....but so long as it says HSPA or HSPA+ in Settings > Status > Mobile Networks, you need not worry