Hi

Last official 501L ROM (android 4.4.2, EMUI 3.0, 400 DPI):
-Taiwan (B103): http://consumer.huawei.com/tw/tablets/supp...tw.htm?id=60006
warning, few supported languages: Chinese & english. But if you root your device, you can add your language with "MoreLangs" and/or "Morelocale 2", available in google play store
Some other recent official 501L ROMs (android 4.4.2, EMUI 2.3, 400 DPI):
- Western Europe (B103): http://consumer.huawei.com/ch-fr/support/p...fr.htm?id=33626
or: http://uploaded.net/file/z4hblokv

- Malaysia (B017): http://consumer.huawei.com/my/tablets/supp...my.htm?id=42841
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But, for a more advanced ROM (OTA, lollipop betas...), you should install a chinese rom devoted to 503L, but fully functionnable on 501L:
** Last official ROM released (B011 = Android 4.4.2, EMUI 3.0, 400 DPI framework with per app DPI setting)):
https://www.dropbox.com/s/ohcbibtxu49e0xj/dload.zip?dl=0
(this pack is ready ton install on 501L with no modifications)
** Last Beta ROM released (B113 = Android 5.1.1, EMUI 3.1, 400 DPI framework with per app DPI setting):
Start from a device installed with above B011.
Then update to B110: http://forum.xda-developers.com/huawei-med...18#post63329818
Then update to B113: http://forum.xda-developers.com/huawei-med...al/rom-t3275540
** add Goolge apps and their sync :
2 possible ways (at your choice):
1)use Huawei store that is already installed on your device:
for gapps: https://www.youtube.com/watch?v=zI2RYZiTl38
for sync services: 
http://a.vmall.com/app/C10029399?shareTo=c...852000000204495 
http://a.vmall.com/app/C10029403?shareTo=c...852000000204495

OR

2) Download the  apk
For apps:
http://www.apkmirror.com/uploads/?dev=google-inc
or http://d-h.st/ztjI
or https://www.dropbox.com/s/zl1usvxkygsody4/L...sForX1.zip?dl=0?

For syncs services:
http://forum.xda-developers.com/showpost.p...07&postcount=31

for the lollipop B011SP05/06 rom's google apps and sync: simply download and install the 3 .apk files attached to:
http://forum.xda-developers.com/huawei-med...al/rom-t3226547
Options:
** root using kingoroot:
http://www.kingoapp.com/
(you can after that switch to superSU using https://play.google.com/store/apps/details?...m.supersumepro)

OR for lollipop, you can also use MobileGo:
http://www.wondershare.com/mobile-phone/ho...roid.html#part2
** add the access in the play store to google+ and many other apps:
http://forum.xda-developers.com/showpost.p...13&postcount=10?
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REMINDER:
** install methods:
https://youtu.be/uEWDTQnstSs?t=2m52s
or
https://forum.lowyat.net/index.php?showtopi...post&p=69086974
(end of post)
or
http://forum.xda-developers.com/huawei-med...14#post57253214
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ALL ROMs in this post are multilanguage except where noted(put your SIM card inside device before first boot), and cover all bands handled by the device. So countries of origin, are here only for information, and are not a limitation of place for use.