Ok first of all forget the smoke release function, you don't need it.
With Smokewinders loaded and in the air:
1) Master Arm On
2) Select first Weapon Select button on PCA (see picture)
3) You should now hear seeker tone (I guess WIP)
4) Press Weapon Release (AKA Fire!) button => Left smoke pod turns on
5) Press Weapon Release button multiple times to cycle through left, right, both on/off.
Hope that works for you!