Hey Rocky
The symptoms you describe are classic dirty nozzle issues. Nozzles are a bar steward to clean. You can clean them, they can seem spotless, but they are tricksy, and paint hides in there. The needle is then not seating properly which affects the spray pattern, and doesn't allow paint to come out right away, but causes it to back up, until it is finally able to get out - giving a big blow out all at once. If you unscrew your needle chuck and very gently move your needle in and out you can sometimes feel if it seems spongy, or sticky, that is one sign of a dirty nozzle. You can also sometimes see if your needle isn't sticking out as far as it should, or if you spray a dot, it could spray unevenly, or spider in one area. You could also be getting bubbling in the paint cup as air is getting forced back (this also happens if air is leaking from threads on the head to, so make sure your seals are good) The blow outs, or blobs at the end of strokes you already know about
If it was spraying well before but isn't now, and nothing has been damaged, then it really does point to a nozzle issue.
45psi is ok for priming and basecoating, though reduced it shouldn't need to be that high (I haven't used that particular brand of paint before mind you), especially through a .5 nozzle. To use your.2 nozzle for detail, you are going to want to be somewhere between 10-25 psi depending on how fine you need to work, to get the control and minimise overspray. So I would play around and experiment until you get your air/paint/reduction just right, as if it isn't spraying through your .5, there's no way the .2 will work. So make sure the nozzle really is clean, and also examine it with a magnifying glass or similar for cracks or other damage, then really spend some time getting it dialed in. This will also help reduce the possibility of future blockages, as when it all flows well it is way less likely to block in the future.