Honor 7 Google Play Services severe problems

I was very keen on the Honor 7 due to 64gb memory, sd card, octacore processor, battery and price.

I ordered one from China, and have had it for 2 days. However, am having severe problems.

When adding an account, there is no option for 'Google'.

I have installed Google Play from the Huawei app store and added an account via Play's startup, and for a while, I could download

from Play store and synch gmail and contacts.

I then started to get error "Error while retrieving information from the server RPC:S-7:AEC-0 ..." when trying to download from

the Playstore.

I have tried many recommendations including :

*Deleting data and cache from Play app, Play services, and framework services.

*Deleting the account and re-adding.

*Full factory reset and adding Play again from the app store.

*Uninstalling Play service updates so it rolls back to factory version and running Play again to force it to update Play services

to the latest version.

Some of the attempts temporarily resurrect Play, and synching, but now I get "Google play services which some of your

applications rely on is not supported by your device"

Each time I try a fix, the time it runs successfully seems less.

Is it worth me perservering with this : for example is it the need for international firmware on the phone? Could flashing a new

ROM get round this?

Is it because I can't add a Google account. It's weird I managed to download loads of apps, but now can't download any!

Or is it likely to be a phone hardware / firmware / memory unfixable problem?

In every other respect, it's a superb phone and I am reluctant to start the whole returns process if possible, however, if I have

to , I must! (Trouble is, I can't see another phone I want as much : my requirements are maximum processor and memory plus must

support sd card).

Any help much appreciated.