A self-contained application produced by the packager on Windows might be usable right away, whether you've taken the InnoSetup or the WiX path.
There's already a long story about the need to resolve msvcr100.dll by the launcher: see RT-25715, RT-37178 and RT-35760.
What seems new with FX 8u20 b23 compared to FX 8 is that I need now to put both msvcr100.dll AND msvcp100.dll to get the launcher happy (seen on Windows 8 and 8.1, 64-bits, didn't try other Windows releases).

I agree with the update by Chris on RT-35760 where he says the packager should put side to the launcher all the necessary DLL files it needs.

Workaround is here to ask the user to install the C++ 2010 redistributable or put directly side to the exe the msvcp100.dll file.