I have tried already tried a variety of settings, but no luck. Can you suggest a trial set of settings related to fan?
I need to clarify: Cura slices fine with the provided profiles (that are not compatible with my printer). I found a similar bug report on Cura 2.4 at https://github.com/Ultimaker/Cura/issues/1417
In that case, the error identified was not the actual error. I tried the "fix" to that bug, which was to export and then import the profile, but that didn't help in my case.
I might also mention that these models all work fine with 14.12 ( my Cura version before trying 3.1).