I don't know why there should be a problem… Here is the result from scratch in a minute or so, using force duration and without messing in the options (since force duration overrides them).
When entering the notes without force duration, I got two crotchets tied together. I selected each of the voices, then force duration, then minim, then re-entered the note (C and G) and here is the result.
OS X 10.11.6, macbook pro retina Late 2013
Opera singer (lyric tenor), photographer, sound engineer, XeLaTeX user and a sometimes music engraver