Sometimes the swashplate just starts separating on its own. In your case, it may be associated with the replacement of your lower rotor hub. Even if you had a pin hitting the end of the slot in the linkage, and you've fixed it, once the swashplate has separated once, it'll keep doing it. Some people have had success putting some glue on it in the right place. Just don't get it in the race. If you've located the lower hub either slightly too high or low, you can get that pin hitting the inside end of the slot when you throw the cyclic stick diagonally. The same is true if you've increased the swashplate travel by moving the linkage on the servo out one hole. In any event, it looks like you have that problem fixed, but your swashplate will keep separating until you do something to correct that.

I use the MicroHeli CNC swashplate and it works great. If you choose to go with the E-Flite CNC swashplate, keep in mind that it seems to be indefinitely backordered (IE: unavailable). Neall

PS: i don't mean to state the obvious, but make sure you reattached those links to the swashplate such that the LONG slot is where the pin is going. There is no need to go back to the plastic lower hub. Big step backwards. Keep the MicroHeli hub.