What settings (if any) from the property pages for the project (such as C/C++, Preprocessor definitions) impact an Arduino project in Visual Studio. I can't get my "Debug" build to work, and I don't understand how the settings are changing from Debug to Release.

Release works fine, here is the output when I try a Debug build:
>------ Build started: Project: VSBlink, Configuration: Debug Win32 ------
1>  AssertTrace.cpp
1>c1xx : warning C4117: macro name '__cplusplus' is reserved, '#define' ignored
1>C:\_SOFTWARE\VSBlink\.vmprogram\.VSBlink.vsarduino.h(3): warning C4005: '__AVR_ATmega328P__' : macro redefinition
1>          command-line arguments :  see previous definition of '__AVR_ATmega328P__'
1>C:\_SOFTWARE\VSBlink\.vmprogram\.VSBlink.vsarduino.h(5): warning C4117: macro name '__cplusplus' is reserved, '#define' ignored
1>C:\_SOFTWARE\VSBlink\.vmprogram\.VSBlink.vsarduino.h(13): warning C4005: '__asm__' : macro redefinition
1>          C:\_SOFTWARE\VSBlink\.vmprogram\.VSBlink.vsarduino.h(8) : see previous definition of '__asm__'
1>C:\arduino-1.0.1\hardware\arduino\variants\standard\pins_arduino.h(28): fatal error C1034: avr/pgmspace.h: no include path set
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

1) Tools, Options, Visual Micro, Compiler: Debug Configuration: I set this to "Debug". Release Configuration I set this to "Release". Are the VisualMicro settings in this dialog documented somewhere?

2) Yes: If I set Visual Studio to "Release" mode, then I get arduino build.

(FYI: I have no Platform in my project. IE: There is nothing in the dropdown that normally shows Win32, etc.)