No, flapperons, or their alter ego, spoilerons, are not required on a trainer, and they may introduce other headaches that need to be accounted for during the programming (the aircraft might pitch in one direction or another when xxxxerons are deployed, thus requiring a third mix with the elevator control or some such).
I cannot say how it's done in the original Turnigy software but with ER9X it's quite simple. It's important to note that each aileron needs it's own servo to make this happen.
[Edit: I'll leave what I wrote in place for the ER9X software, but after posting, I decided to look at Richard's video that I post a link to further down, and realized that the video I selected is about adding 3 levels of FLAPS in the original Tunrigy software, so perhaps it'll explain what you need if you are not using ER9X! Richard also shows a bunch of programing tricks in ER9X so subscribe to his channel... excellent stuff. ]
My example in ER9X:
CH4 100% AIL
+ 70% Max GEA
CH6 -100% AIL
+ 70% Max GEA
Now, if this all lines up in your window, it should be legible.
Channel 4 servo operates one aileron. Channel 6 operates the other one. I added a mix to each channel, using the switch marked gear and when the switch is engaged, it adds 70% up to each servo, thus my example would be for "Spoilerons", simply use -70% instead to make them flapperons. In ER9X you can link any switch or pot or stick to any other switch, pot or stick.... I think the original software is more restricted...
On the aircraft I was programming, I also have 2 rudders (F-22) and I've programed the rudder switch to add + and - 70% to the two rudder servos creating an air brake by having the two rudders move towards each other. The rudders will still respond to the rudder stick as the ailerons will to the aileron stick.
The best suggestion I have for doing these sorts of things is to make up a little board with a full complement of servoes (I just used the cheapest 9g servoes I could find), an 8 channel receiver and I added the smallest motor and esc I had so that I could program away on this board and see how things work out without actually playing with one of my models. An excellent view of such a board can be had in Richard's excellent series of videos for the 9x with ER9X software:
http://www.youtube.com/watch?v=L3Mw6jDlUzIAs for the balance lead.... again, I don't have any pictures to show how it's done, but it's quite simple really and I'll try to make a diagram:
cell #1.....cell #2
+{IIIIIIIIII}- +{IIIIIIIIII}-
1.........2..........3
The colors on the balance leads seem to vary depending on who made them, but the -V is always black (3) and the in between balance leads go to each +- connection (2) and the other edge wire opposite the black wire is connected to the + end (1) of the entire pack so the two outer wires display the full voltage of the entire pack. In this case using the middle wire and either of the outer wires will read the one cell on either side.
It's hard to draw this with characters as spaces are ignored so I had to use periods instead of spaces, please ignore them. The two battery cells are shown connected in series so if you use a voltmeter and measure between 1 and 3 you will get the full voltage of say 7.4V. If you measure between 1 and 2 OR 2 and 3 you will get 3.6V. So on our 3 wire balance plug, the black wire goes to 3, the middle wire goes to the wire that connects between the two cells @2 and wire on the other edge of the plug goes to 1.
I hope this helps,
Regards
Christian