My side to side was cured by just leveling the swash plate. I guess the easiest way I know how to explain it is to try and trim it with the little sliders (trim tabs) on the tx (transmitter). If you can't dial it in with the tx then your going to have to mechanically tune it. If you follow your guide it will walk you through setting the 4in1, or 3in1 I think on the v2 of the cx2 to correct yaw or setting your rudder. Now if you can't correct your forward/back or side to side with the tx you will have to adjust the servo linkage arm length. Soloboss covers this in the guide. Last but certainly not least is the flybar. If it's out at all you can get a variety of things happening. Usually for me when the flybar is a mess it will roll around in a small circle like it's going down the toilet...thus TBE or toilet boil effect. You can get these little guys dialed right in. Then you will have nights like the one I'm having when you just can't fly it at all! Two flights....3 broken blades! It happens