Try running it as an administrator by right clicking the FH icon and selecting 'Run as administrator'.
If that doesn't work then I've noticed you said you put your window to full screen? try keeping FH to a windowed screen.
You may be experiencing an ogre glitch. If you can get onto the home screen okay, then go to;
Options >> Video >> RenderingSubsystem >> Direct3D9.
If you can't get onto the main menu then follow these instructions:
Local Disk (C:) >> Feral Heart >> ogre (.cfg)
Open the Ogre in notepad or another word document then replace it with this:
Render System=Direct3D9 Rendering Subsystem
[Direct3D9 Rendering Subsystem]
Allow NVPerfHUD=No
FSAA=0
Floating-point mode=Fastest
Full Screen=No
Rendering Device=Monitor-1-Intel(R) HD Graphics
Resource Creation Policy=Create on all devices
VSync=No
VSync Interval=1
Video Mode=800 x 600 @ 32-bit colour
sRGB Gamma Conversion=No
[OpenGL Rendering Subsystem]
Colour Depth=32
Display Frequency=N/A
FSAA=0
Full Screen=No
RTT Preferred Mode=FBO
VSync=No
VSync Interval=1
Video Mode=800 x 600
sRGB Gamma Conversion=No
Save and restart you computer for it to take full effect.
Try these first. If this doesn't help I have plenty more options for you to try - so just reply for more help and I'll help you.
Please let us know if this has managed to help you out at all.