I was getting errors with FE Shadownet before and I fixed it. There's multiple things you wanna have done. Make sure your Fable TLC copy is not in ProgramFiles or ProgramFiles(x86). For Some reason FE doesn't like ProgramFiles and just crashes and gives you errors when fable is in there. If you have a steam copy just go to your steam steam apps common fable tlc and move it onto your desktop or just go outside of the folder program files and paste it out there. make sure your copy and pasting the fable folder and not just dragging it so there will be two copies of it. Another thing that fixes FE Shadownet is going in the config file in Shadownets directory and change <UseRegistry>TRUE</UseRegistry> to FALSE, just change the TRUE to FALSE and then you want to make sure that the install dir is set to your fable tlc copy that is outside of programfiles or programfiles 86 and be sure that there is a \ at the end of the fable dir like this <InstallDirectory>E:\Fable The Lost Chapters\</InstallDirectory> and all of that should fix it, good luck!
EDIT make sure you do all of these things, I have all of them done and my FE works great.