DOSBox Libretro crashes as soon as running a game

I want to integrate my dosbox games into retroarch (1.3.6) using the dosbox libretro core (DOSBox Git (5deb)). I can load and start the dosbox libretro core itself, which sends me to the dos prompt. From there, I mount my games directory to C, but as soon as I start any of my games (which work with standard dosbox settings), I get the error message “retroarch has stopped working” (Windows 10). This is the log file from retroarch: http://pastebin.com/c79HEtyT

However, I don’t see anything interesting in there and retroarch doesn’t log anything new after starting the libretro dosbox prompt.

I also tried to load game-specific working dosbox config files, but the outcome is the same: libretro dos prompt working, running game crashes retroarch.

What could be the problem and what can I do to find out it’s cause?