Galaxy Ace video player and custome ROM

[deadlock4400]

trying to post a question on the link below:

[ROM][CM10.1.4] - modded - [stable-20130826(update 0905)] / [Nightly-20130921] - OTA - xda-developers

but unable as i am a new here. currently i have a Samsung Galaxy Ace GT-S5830L ARM1136 800 MHz (Samsung Galaxy Ace S5830 - Full phone specifications). How can i install in a proper way the latest stable custom ROM like JB 4.2.2 ??

And if i want to use a video player in this GT-S5830L which player will play smoothly *.mkv, *.flv, and many other HD files ??

Thanks in Advance