MediaTek "Iphone" from Kuala Lumpur

[android master]

Hi thanks for your help in advance.

I'm absolutely new to all this but I tried to get as far as I could without help until now I kind of lost my good will. 
So I bought this fake-Iphone in Malaysia and yes I knew it was fake but super cheap as well... wanted to sell it and bla.
Right now I'm in a situation where I decided to keep it for a while as my own phone.
It's a mediatek version and the asian guy I bought it from let it look like it's an Iphone, tried to hide all the features... 
Now I used an app to look which version of android would suit this fake phone the best and it's one or two versions down from the current installed one. I tried to downgrade it with an update.zip file of ice cream sandwich 4.0 but Mediatek won't let me flash it from just the phone so downloaded a Smartphoneflashtool on my Laptop but there is no Scatter-loading-file inside the update.zip data to flash. 

Can someone tell me where I get the right Firmware to downgrade this stupid phone please   Hope it'll work properly with less laggs after this.

please give full info about mobile your are using