

To the second and third issues, I think they happened because of bad settings in the wave soldering machine, and/or not prepping the board beforehand. Maybe the wave was to high, or the speed too slow. Many times you have to cover the smd components with a bit of painters tape. Even the orientation of the board on the frame can matter.
Don’t know about the glue thing, the smds were put by a machine, but they would move like the one in the picture if you didn’t set the machine right. I can’t say for sure with that resolution but I think those white things are the shiny reflections on the pins/solder. I will look into these smd glues tho, that could come handy.
And about the tape I have to say that my experience with wave soldering is not very vast, literally just one place, but they used painters tape, of the cheapest kind, and it worked just fine—no melting (it’s paper?), and no burning since the solder doesn’t get that hot (~200°C), the tape might stay a bit wet from the flux also idk.