It's pretty simple IMO.
First up, the charts actually start at a certain point in plant development. It's hard to define, but the main thing to realize is that "Week 1" doesn't mean the first week they sprouted, rooted, etc. It's based on the system where larger-scale growers have a nursery, veg room, and bloom room. Week 1 is when plants graduate from the nursery to veg. Of course different growers define this differently, but we're not talking about baby plants. More like teenagers.
As far as the veg/bloom charts go, I use veg until I see flowers, then immediately start following the bloom chart. Ideally I'd like to switch to bloom nutes a couple days before they start to show sex, but that can be hard to predict until you're really familiar with your strain. Same goes with the transitions between the early, mid, and finishing bloom nutes. That's more an issue if you're using a lot of their products - which I don't want to get into a debate over whether people should or shouldn't - but again that's something that gets easier as you get more used to how long your plants take to finish.
Regarding the strength to use, that's always gonna be something each grower determines themselves. The pH Perfect nutes are supposed to be fine at full strength for any plants but you should do what you think is best. I always, ALWAYS start out at half strngth AT THE MOST when I'm running a new nute line, strain, or wahtever. It's always smarter to underfeed than overfeed. You and I could grow the exact same strain on exactly the same nutrients and what burns my plants might be just right for yours. We each have to dial our nutes in for ourselves. It looks like you're on the right track.
I understand it for photos but I used it based on them weeks in flowering for autos and they seemed to work fine, I gave her 2ml (full dosage) once a week and I found no problems.
