Linking between projects - c++

Question

I have a solution with 2 projects in it:
The first one is called Engine and it has 3 classes: Backbuffer and Vector2 and CTimer. It is of type Console Application DLL, links winmm.lib, has all members in namespace "Engine" and if I build it (only this project) it compiles.
The other one, Game, links dependency for project Engine, is of type Win32 project, has additional include directories $(SolutionDir)\Engine\, has "Link Library Dependencies" set to true. And it does not compiles.
Both projects are compiled with "/MD" flag.
I don't know for sure if the problem is caused by VS12. Tried lots of solutions to similar errors but with no results for me.
The problem seems to be it doesn't compile the .CPP files. Thought if I compile only the "Engine" project, it compiles perfectly.
Errors:
1>------ Rebuild All started: Project: Engine, Configuration: Release Win32 ------
1> BackBuffer.cpp
1> CTimer.cpp
1> Vector2.cpp
1> Generating code
1> Finished generating code
1> Engine.vcxproj -> G:\Ubisoft\HumansVsZombies\Release\Engine.dll
2>------ Rebuild All started: Project: Game, Configuration: Release Win32 ------
2> CGameApp.cpp
2> CGameObject.cpp
2> Main.cpp
2>CGameApp.obj : error LNK2001: unresolved external symbol "public: void __thiscall Engine::BackBuffer::reset(void)" (?reset#BackBuffer#Engine##QAEXXZ)
2>CGameApp.obj : error LNK2001: unresolved external symbol "public: void __thiscall Engine::BackBuffer::present(void)" (?present#BackBuffer#Engine##QAEXXZ)
2>CGameApp.obj : error LNK2001: unresolved external symbol "public: __thiscall Engine::BackBuffer::~BackBuffer(void)" (??1BackBuffer#Engine##QAE#XZ)
....
2>G:\Ubisoft\HumansVsZombies\Release\Game.exe : fatal error LNK1120: 12 unresolved externals
========== Rebuild All: 1 succeeded, 1 failed, 0 skipped ==========
Thank you !