Ken always knows his stuff and when I started playing years ago got me straightened out on the string tuning notation. I was breaking strings like you and my problem was related to exactly what he was talking about. Those J64 should work fine for you but since they are not and you have a tuner there are a couple of things you might want to check. First, check to see what the calibration on your tuner is set to...........is it 440? Second, try this tune your base string to where there is just enough tension to get a clear sound. Not to floppy and not to tight. Check and see what your note is with your tuner. Tune it to D.............middle string.........tune it to where it is making a clear note, again not to tight and not to loose.............check it and tune it to A...........when you get to the melody strings repeat the process and see what note they are playing. This is where I was messing up when I started......I was trying to tune way beyond the d, going into an entirely different octave.
On the other hand, as Ken points out your fret board may require entirely different gauge strings because of its length......until you get it worked out I would tune CGc............of course that is your choice..............for me DAA and a noter or DAA and fancy finger hopping as I call it, is the way to go as a beginner and an advanced player. This link might help you.............
http://www.jcrmusic.com/Learning.html
updated by @salt-springs: 01/27/16 09:49:53AM