Sorry that things have got a bit heated here, however I appreciate having seen multiple methods to tie down the roof as this was the part I was most unsure about.
I find fixings a minefield in general. Its nice to see what alternatives are available for different applications and its also useful to have exact specs for things. Too often the advice is to use nails or screws but with no specification of length and width dimensions.
@dlockers I was watching the Oakwood Garden Rooms build last night, where he does it solo and with only basic tools. Very useful series. I think their 'build packs' are very expensive though (now £130) for what is essentially a parts list but did you find it useful? I noticed he intended to use a nail gun but forgot it early in the series so proceeded without, by separating the nail gun nails and using them by hand. I would not have known that could be done.
Thinking about hand nailing in combination with a screw to pull the joint tight first. Its only 4 nails per upright, two top, two bottom which on a 16 stud segment will only be 64 nails. Obviously plus a few extra here and there, but certainly not many really.