Bug#772898: win32-loader testing and newer fails with TRANSLATE error
probably I have found something more.
I tested in a VM with a more recent windows version, therefore I cannot
sure that this is the reason you saw (having to run win32-loader with
compatibility set to windows 7 on a windows 8.1 32bit).
I used the version from .
Because you already hinted to the direction of loading nsisdl.dll I
watched an installation attempt by ProcMon  and found after the nsisdl.dll
was accessed it tried to load a file libwinpthread-1.dll which it could not find.
Opening nsisdl.dll in Dependency Walker  it is shown that it is really linked
So I downloaded package mingw-w64-i686-dev_3.2.0-2_all.deb , extracted the content
to some directory and started a cmd with elevated rights and added the path.
Then started win32-loader from this cmd and it worked and finished installation.
So this dll could be added to the installer and extracted along the nsisdl.dll, or
the dll needs to be statically linked against libwinpthread-1?
PS.: and yes, it booted as expected even on windows 8.1 into the installer.