Should be here in a couple of days, I am seriously pumped for this so much so that I tried pressing something in the vice, I used the top of my weed grinder as a base and a 200g weight as a press that I heated with a blowtorch. I tried a 0.25g

and used a blowtorch

seemed to work OK.

which made a decent size dab, so this is just manual and guessing everything. I tried a half gram and it did not work very well

so it's obvious that the quantity must be tuned to the press.
After rewatching all the videos, a crucial step is mostly not shown due to the close up, but on all the slugs from the small one to the Fat Mac, right near the end of the press the last quarter inch the outside cylinder of the Slug will pop up, when this is seen in close up it appears that the pressure has been released but this is not what happens.
So it seems the correct technique is (with this 4 min slug) to heat for four minutes while slowly depressing the plunger and when there's about a quarter of an inch left to go that's when the rosin should begin to flow and then the last part is pressed over the next 40 seconds or whatever.
What the video in the O.P and see at around 5:30 it has the last little bit and it is slowly being squeezed then at 5:44 you see the cylinder pop up, then you press the final few millimetres. It seems pretty fool proof and repeatable, with this new insight into how it works I'm expecting to get a good result first time, we'll see next week.
Here's the pop up thing shown more clearly on the small slug. It happens at 1:52