For the interested parties:
Trying to compile Dark Shader library along with Sparky's Collision library, raises a linking error (symbols already defined):
1>------ Build started: Project: Project, Configuration: Release Win32 ------
1>Linking...
1>shaderdata.lib(shaderdata.obj) : error LNK2005: "bool bInitialised" (?bInitialised@@3_NA) already defined in SC_Collision.lib(dllmain.obj)
1>shaderdata.lib(shaderdata.obj) : error LNK2005: "bool __cdecl CheckInit(void)" (?CheckInit@@YA_NXZ) already defined in SC_Collision.lib(dllmain.obj)
1>Release/Project.exe : fatal error LNK1169: one or more multiply defined symbols found
1>Build log was saved at "file://c:\Visual Studio Projects\BUGS 2010 DGDK7.4\Ejemplo conflicto SC collision y DarkShader\Release\BuildLog.htm"
1>Project - 3 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
Sample project raising the linking error attached.