Hello, I am trying to compile the unreal engine 4 from source code on github. But I made a mistake while following the official guide. I did download the release branch and instead of the 4.8 and it still fails to compile. Now I’ve downloaded the 4.8 branch and wonder if it is possible to copy and paste the rest of UE4Editor data ± 3Gb not have to download them again.
Thanks for all. 
Hi Micoli
What do you mean by download? I would recommend to clone it at least.
git clone https://github.com/EpicGames/UnrealEngine.git
The line above will clone the repository and will checkout the branch 4.7. If you want to use the 4.8 branch go into UnrealEngine folder after the cloning is finished and do this:
git checkout 4.8
You will be in the 4.8 branch. Now you start the setup which will download the dependency files
./Setup.sh
After that generate the project files which is needed to compile UE4
./GenerateProjectFiles.sh
Now you can compile
**make UE4Editor ShaderCompileWorker UnrealPak UnrealLightmass UnrealFrontend **
Drink coffee or orange juice and relax until it finished 
yaakuro