Personally - I don't mind when DarkGDK forum goes into the C++ or .Net topics - its all related to me.
Sparky's DLL for DarkGDK. Yup. Good Move. Personally - I consider Sparky's such a staple - I copied the LIB to the c:\program files\the game creators\darkgdk\lib directory - (what ever its named - where all the DarkGDK lib's are. Similiarly - I copied the sparky header file SC_Collision.h to the DarkGDK include directory with the DarkGDK.h file.
This way I simply use like the DarkGDK stuff - the directories are all set up already for each DarkGDK project - and I go with a simple:
#include <SC_Collision.h>
Good Luck.