I tried using the technique mentioned in the video and was able to get it to work.  You need to make sure that when you start Logic you specify the number of INSTRUMENTS..  I found, however, that the method in the video made it much more complicated for my use (YMMV).  I've gone back to setting up a template in Logic starting with just one track, entering an Aria stereo instrument for that track, the doing the whole process over for each additional instrument.  If you try copying the channel strips it will work, but you get the same instrument as the original track.  If you have a separate Aria player for each track, you can use instruments from Finale, GPO, JABB, and even the samples that come with Logic if you change to the default player.  The drums in Garrison leave a lot to be desired, for example, and the Logic ones have more flexibility.