Your dll for release is monolithic while your DLL for debug is multilib. This means you have an issue to me.
Why are you changing two things at once. Please try doing an monolithic debug or do an multilib release build next. Do not try to change them both at once till you know more.
Note, changing the compiler makes it three things at once.
You should decide are you doing an Static or DLL build?
If Static, I suggest multilib.
If DLL, I suggest monolithic build.
If you decide to do multilib build, you need to list more libraries than just one. The base dll and core dll is a good start, but there is other wxWidgets libraries that might need listed. The order libraries are listed matters with some compilers I have no idea if it matters with MSVC or not.
Here's a possible wxWidgets build command, I have not tested it, but it should work.
it is for monolithic debug unicode DLL.
remember to change dir to build\msw
CALL "%VS80COMNTOOLS%vsvars32.bat"
nmake -f makefile.vc USE_XRC=1 SHARED=1 MONOLITHIC=1 BUILD=debug UNICODE=1 clean
nmake -f makefile.vc USE_XRC=1 SHARED=1 MONOLITHIC=1 BUILD=debug UNICODE=1
Tim S