For Pecheneg, think Custer. A command of wagons defended by men on foot under the control of the CnC. But unlike Custer (who split his force and sent his subordinate off elsewhere), you get subordinates with your mounted on the table.
The notes at the end of the blurb need to be taken literally.
You must take foot. The foot must be with all the baggage. Therefore, you have two choices (a) a baggage command (which can be defended with TF) and all the foot in that command, or (b) baggage in only one normal command (i.e. one command with command baggage and all the foot, and no baggage in the other commands).
If you replace the foot with WWg, the above applies to those WWg (but in the baggage command and you lose the TF option).
Re p. 14, the 'additional troops' rule still applies. Each train element is 1 ME. Each of the allowed troop elements are 0.5 ME, so complying is not a problem (although I concede you would need 4 commands with 2 Bg each to get the full 16 foot in a baggage command, but the list only allows up to 3 commands. That said, you could still take all the foot if you go with (b) above.) If you take WWg instead, they are train, so no problem in a train (i.e. baggage) command.
Moral works as normal. With a baggage command, the other commands get the usual ME benefit. Any foot or WWg in a baggage command add to the ME of the baggage command (and the total of the army in the usual way).
You cannot take 3 baggage. If you follow (a) above, you get 4-6 in a baggage command. If you follow (b), you get 1-2. (I don't think you can go with 0 baggage as I would suggest you have to have at least 1 for the foot to go with.)
For command, if you go with (a), then the CnC (and only the CnC) can use his PiPs on elements in the baggage command as per the rules. If you go with (b), then again as per the rules, that command will have a general but need not be the CnC.
From a tactical point of view, (a) essentially gives you a well-defended baggage command on the edge of the table with all the usual army baggage ME benefits, while (b) enables you to put down an awkward circle of WWg more towards the middle of the table (or a slightly more mobile WWg formation) at the cost of those benefits.
Anthony