I understand your first post. Can't think of why your pressure would drop unless the oil line had come off completely, which you say it hadn't, just apparently loosened a bit and pulled back on the fitting a little. It sounds like you may have air in the system, not sure how that would occur with the system intact, even if a hose is leaking a small amount. I would be interested in seeing how much oil is in the filter, since it's a vertical mount, you should be able to carefully take it off and see if it's full as well as see how much oil comes out of the lines. The accusump should be full now, right? Next I think I would want to empty the filter after noting how full it is, and reinstall, empty. Get someone to turn the ignition on, but not start the engine, discharging the Accusump. Have the person turning the ignition watch for any rise in the oil pressure gauge and (this is why I suggested having someone else turn the ignition on) you watch the lines that you have pictured for any leakage. After giving the Accusump time to fully discharge, remove the filter and check oil volume again. If you see no other leaks and the filter is full, reinstall the full filter and check the engine oil level. If all looks good, start the car and count to five, watching for oil pressure rise. If nothing happens by an easy five count, shut the engine off. You are not likely to hurt the engine in that amount of time if you don't rev it and if you don't get oil pressure you may have a problem not related to the loose line. Don't get confused and keep notes while you are trying to diagnose a problem. I would next take the Accusump out of the system and again start the engine for a short period of time and see if you are getting oil pressure. The Accusump could have a problem or you could even have a failing oil pump, but you should be able to get some idea if you keep in mind that the problem may not be readily apparent and you have to absolutely eliminate things that might be the problem one step at a time.