Not entirely sure they would share settings and registry entries so may interfere with each other but not to any notable extent.Keep checking. I have been running v7.7.1.0 from an automatic update a couple of days ago.
I am sure that Alexander will give the definitive answer but I would expect multiple instances to run independently without interference.
The most common cause of the spouse gender issue is a save issue in FTM where it saves the wrong gender. As has been said manually changing it and changing it back seems to fix the problem. It's down to how FTM writes out the gender in the GEDCOM file which of course is what FTAnalyzer uses to check the data.