The single most important thing you can do to help ensure the success of your Solution development project is for development team members to thoroughly read and understand this document. This guide should tell you most of what you need to be able to successfully design and develop a product using FESF.
Looking at the FESF Sample Solution will illustrate where the various header (.h) and type library (.tlb) files are located in the FESF development kit.
While the structure of your source tree is certainly up to you, we recommend locating your Client Solution directory as a peer (that is, on the same directory level) of the UM_FESF directory. We think this will make referencing the FESF components easier.