Kodak 1A Autographic questions, frame counting etc

Since I'm always up for a challenge, my mother gave me my grandfather's Kodak 1A Autographic probably circa 1915. It had been stored well and I think my mother even used it as a kid!

I did the necessary mods to fit the 120 film, spacers for the spools, some black card stock to make the film fit and slide along better. Popped in a roll of Pan F 50, just to see what happens. It was trial and error, mostly error in the first 3 frames to get the frames correct

I Finish the roll not knowing what to expect and voila! Images! They came out a little under exposed, could be I used the iPhone light meter (not accurate) or something else so I know to go down a stop perhaps. All in all good stuff, very pleased. Fun.

My question is on e of the frame counting. Someone, I can't find the thread had used 8.5 turns after the arrow is at the right hand side. Then 2.5 turns every shot, 2.5 turns gave me the space of about a 6x4.5 image. Maybe 2 and a 1/4?

Another question is that when drawing the bellows out it is supposed to lock at the 100 ft focus point and then the knob will move it along the focus meter. It does not lock anywhere along the track, so I pull it or push it to the correct focus. Why doesn't it lock? I don't want to fuss with it too much but if anyone has any suggestions that would be great!

attached are some of the photos, they are really very good, sharp. Lovely.

thanks
Adria

The results look good.
The sequence will change as you wind - more turns at the beginning, with fewer turns at the end.
Can you make any use of the printed numbers and the window instead? With my 616 camera, I can just wind two sets of numbers at a time.
Failing that, retrieve your backing paper, mark out where the frames (ideally) would start and end and then wind the backing paper through with the back open, counting turns as you go.

That makes sense since the first 3 shots were jammed up together and the last 3 had a lot more space. I will try with the backing paper next time, it's already gone... I'll do 2.5 turns then 2 or 2.25 towards the end.