In your ogre.cfg file(located in the main fh folder), you can change you subsystem ^^ Just right click, open with, notepad, and replace the following 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-AMD Radeon HD 7700 Series
Resource Creation Policy=Create on all devices
VSync=No
VSync Interval=1
Video Mode=1280 x 800 @ 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
If it is already set at Direct3D9, just do this:
Rendering Subsystem=OpenGL Rendering Subsystem
[OpenGL Rendering Subsystem]
And it should work ^^
~ Whisper