Great bikes Mike and welcome. Lovely to see the selection of Ace bars!
The A10 looks just superb and a worthy stable mate for the other beasts.
Starting in the 30s Fahrenheit without a choke could well be a pain - mine sulks a bit when the temp gets down to about 3 Centigrade. Holding a hand over the intake while kicking it usually does it, without sucking the skin off the palm, but a choke slide would definitely be better! And for you with that stack on the end, no space for the hand methinks.
Re the smoke from the rocker box, could it be that someone has put a 'breather' hole in one of the rocker cover plates? I think there was a misguided fashion for doing that a way back. Someone had done that to my front cover, but then thought better of it and blocked it up again. I'd have thought it was unlikely that visible fumes were coming out of a gasket joint, otherwise that beautiful creation would be covered in oil up top. In any event, not all that hard to take on and off. But you might want to get a 'pushrod comb' tool if you're thinking of taking the rocker box off completely, as the pushrods are a pain to hold while the box with rocker arms inside is put into position on top of them. But anyone prepared to play with Laverda cams will have no problem with a bit of British Agricultural Engineering, I'm quite sure!