There are some improvements in midi - specifically clock - that I worked on that are not in the current (181101) release.
So this is greatly improved in the next release, but that doesn’t help you much right now.
If you were feeling adventurous you could get the more recent midi.lua, replace that, stop/start norns and then update the scripts with the new midi fu.
I have an example test script which should work with external sync. You’d need to work from here to update playfair or foulplay.