I just downloaded 4.8 from GitHub and compiled it.
The build works fine.
But when I create a project based on the templates, say the FPS template, it load with the following errors:
Do the animation files exist ? The should be in something like *YourProject/Content/FirstPersonBP/Animations *
Do the source animation files exist ? They would be in something along the lines of Templates/TP_FirstPersonBP/Content/FirstPersonBP/Animations
Im also curious about the UE_Mannequn folder. How did you create this as the only folders that I would normally expect to see there are: Animations, Audio, Blueprints,Character,Maps,Meshes, Textures