FleX - the project file of 'flex' is missing

Hi,
I just downloaded FleX SDK 0.9.0 and tried to compile flexdemo,
but VisualStudio2013 says the project file of ‘flex’ cannot be found.

Where is the project file of ‘flex’?

I just tried it in VS-2013 and yes, it shows that flex cannot be found, but no need to worry about that. Just build the project and it will work just fine.