LNK1181 cannot open input file 'obj\filename.obj'

[d_stranz]

Error LNK1104 cannot open file 'qmapcontrol0.lib' Citymap PathToQMapControl\QMapControl 0.9.7.9\QMapControl\Samples\Citymap\LINK 1

Because you built your solution from Samples.pro, not QMapControl.pro, one directory level higher. Samples is not the top-level directory when you unzip the distribution file, QMapControl is. Try again using QMapControl.pro as input to VS. Starting there also adds the Samples projects and sets them to be dependent on QMapControl0.lib/dll, so these will be built too.

Do I have to specify for nmake that I want to target 64bit?

It looks like you opened a 32-bit Developer Command Prompt window. If you have only a 64-bit Qt installed, this won't work. There should be a corresponding 64-bit Developer Command Prompt option on your menu. Use that.

Edit...

On my MSVC 2015 install, there is a submenu for "Windows Desktop Command Prompts". Use the "VS2015 x64 Native Tools Command Prompt" from that. If you don't see it, make yourself a .bat file and put this line in it:

%comspec% /k ""C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat"" amd64

%comspec% /k ""C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat"" amd64

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(Change the path to point to where you have MSVC installed if that isn't correct). Put a shortcut to this .bat file on your desktop and you should be able to double-click it to launch the developer window.

[HappenedTomatoes]

Thank you so much, building QMapControl.pro finally worked!