As the new test has not been executed by Marvin because of the timeouts, I thought it might be a good idea to trigger a test run manually: https://testbot.winehq.org/JobDetails.pl?Key=131337 And it crashed on Win7 (ACCESS_VIOLATION).
So I tried again on Win7, with reporting successful tests enabled: https://testbot.winehq.org/JobDetails.pl?Key=131343 No ACCESS_VIOLATION this time. And running it again on win7 without reporting successful tests, it worked again: https://testbot.winehq.org/JobDetails.pl?Key=131344
So it looks like the test sometimes crashes on Windows (7?), but I'm not sure how to debug this.