OK
You’re TA and the FCB are set to channel 2 great, done.
Does the TA respond to program changes? If not go to TA instructions and make sure it is set to accept program changes. OK got this going if not already.
On the FCB as far as the expression pedal pick a cc# if you have been using 8 that is fine you can stick with that.
TA pick one patch to play with till you get everything up and running also make sure it is a user patch and not a preset! Within the user patch make sure the TA is set to respond to cc8 if this is the cc# you chose on the FCB.
Next you have to tell the TA how to respond to the cc so set your thresholds just for the sake of getting it up and running just stick with one thing like the gain and set the threshold from low side of pedal 1 and high side 8 and store
This is just basically a check list hope it helps, when you do get it going don’t forget you can target several things in the same patch all with the same cc#. So when on the low side to high side of the pedal you can have stuff going on like tre 6-9 gain 8-3 bass3-5 and so on, don’t forget the thresholds can work in reverse (gain 8-3) while. With this same patch on the FCB, processor of your choice can also be responding to cc8 as well and say low side the target can be the output of a delay from 0-25% output of a flange from 40%-0 and so on, with most processors you can target anything.
Keep in mind once the midi channels are set on, they remain constant. CC#s are different it is per patch on the TA and usually any type of processor. So if you are having a problem with a patch check to make sure that the cc# is the same as the pedal board in our case 8.
The TA and most processors can respond to many cc#’s within a single so if you have 2 expression pedals one 8 and the other 10, maybe with patch whatever on the TA the gain and treble with respond to the first pedal and the second would handle maybe presence you know whatever.