Hi Keith,
It's so easy to make a mistake with all those connectors. You wouldn't be the first person reseating a plug the wrong way around. Double check that all pins 1 (arrow) are at the right place. Maybe you can see which side was which in your photos, one side is full plastic and leads/pins are visible at the other side.
I would first try to get the 'scope more or less working. If you start now to resolder or whatever, you will never know whether you introduced new problems or made things better.
Also leave the PS alone. It's in tick mode now while it was not previously. So the tick mode is most likely caused by a fault elsewhere. Again this makes me think of a wiring fault.
