The last challenge I am having is getting the filament to pass through the y-splitter with 100% confidence. I have sanded the inside of it to make it a little bigger, but the filament still gets stuck. The tip shaping on the ends of the filament looks great like the ones in the green box. circled in red is where they get stuck. I also tried loosening the bolts in hopes of making this area a bit bigger.
Can you take pictures of your tips... In this picture, it sure looks like there is something in the Y adapter. Any debris left in it can jam it.
There is nothing in the Y adapter by itself that would prevent normal size filament from passing through... So if it loads, it should unload with the same ease of motion.
Make sure your PTFE tubes are fully inserted into the pockets below the connectors and that their passages are flared, so there are no sharp edges for anything (like the lip of a bulge) to get caught on.
Bill