Ok, I think I figured it out - the problem was that the component J3, that didn't move with the rest, is defined as "Board side" "Back", whereas all other components seem to be "Board side" "Front".
I had also noticed that, when I change the J3 component from "Move and Place": "Lock footprint" to "Move and Place":"Free", then save the PCB, then close PCBnew, then reopen the PCB design, then check the J3 Footprint properties again, it has "Move and Place" set on "Lock pads", not on "Free" as I previously saved it with; not sure why this happens, since there is no keyword like 'locked' or 'placed' in the
.kicad_pcb (which, I believe, controls those properies) - but apparently, that was not the cause of the block selection move problem.
So, this is how I can finally perform the move - here is the imgur post with all images https://imgur.com/a/shjHG :
- Open the PCB, open the Footprint Properties of J3, make sure "move and place" is not set to "Lock footprint" ("Free" or "Lock pads" is fine); and change "Board Side" from "Back" to "Front":
- As soon as you've made that change, note that the J3 pads become slightly offset
- Zoom out, make a block selection, press Enter to accept default settings, start moving - notice now the pads are drawn as moving with the rest
- When you release the mouse, notice that might get some white ratsnest lines, though they are, apparently, "fakes" (though they don't disappear with plain zoom in/zoom out - only if you do a block selection over them)
- The PCB layout has been moved, but the pads of J3 are still wrongly offset - no problem, just show the Footprint Properties of J3, and change "Board Side" from "Front" to "Back":
- Yup, the PCB layout is now moved, and J3 is in its correct Board Side state (Back), and its pads are correctly offset - the block select move procedure can be declared done!
So, I guess this is it - although, it is good to ask: is this all there is to it to doing a PCB layout block selection move?
Also: is there an easier way to perform such a block select move, without the need to manually change footprint properties?