Optimized compile in VC express

Ok first off , the release build works fine and compiles no problem.
also:
xp sp2
visual studio 2006 v8.0
directx-DSK 9.20.1057.0 ( aug 2007 )

i wanted to fiddle with the optimized build from the TGEA SDK.sln ( same project file i use for the release build ) but i'm getting the error

1>------ Build started: Project: Torque Game Engine Advanced, Configuration: Optimized Win32 ------
1>Performing Custom Build Step
1>Performing Custom Build Step
1>Performing Custom Build Step
1>Performing Custom Build Step
1>Compiling...
1>cl : Command line error D8036 : '/FoC:\Torque\TorqueAdvanced\vc8\Optimized' not allowed with multiple source files
1>Creating browse information file...
1>Microsoft Browse Information Maintenance Utility Version 8.00.50727
1>Copyright (C) Microsoft Corporation. All rights reserved.
1>BSCMAKE: error BK1506 : cannot open file '.\optimized\audio.sbr': No such file or directory
1>Build log was saved at "file://C:\Torque\TorqueAdvanced\vc8\Optimized\BuildLog.htm"
1>Torque Game Engine Advanced - 2 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 5 up-to-date, 0 skipped ==========

i'm more concerned with the /FO line ( a rebuild will probly fix the audio.sbr one ) .. of note , changing the output to example still gives
/FO../example not allowed with multiple source files
error .. so i'm guessing this is more of a VS issue.

/FO ( guessing ) is just "file out" so it looks like a setting somewhere is wrong .. but i know how C++ code works , i dont know every single menu in the IDE or where it could of gottn this from.

Also i dont know if building the optimized version is even supported.

Any help would be welcome.