Well I tried to run a test print, just to get to a point where it at least loads the first tool, then forms the end of that tool before switching to the next, but now I can't even get that far. For some reason, the first filament never reaches the hot end and starts printing air. I made sure all 4 ends of the filaments were snipped at a clean 45 degree angle, and fed just before the Y adapter, for the few prints I tried. Every time, the first filament reaches the Ender 3's extruder, but for some reason does not get fed to the nozzle all the way. And also, very strangely, sometimes the MK2 would randomly start feeding in another filament before the first one, and THEN start feeding in the first filament, and run into a traffic jam in the Y splitter because the other one is already fed in. It happens, I would say...every 1 out of 3 attempts with the same gcode. And when I ignored the first filament not actually printing out and just let it continue to the next, when the MK2 tries pulling out that first filament, the gears may be spinning but it isn't always pulling the filament through. I have to yank on the filament sticking out of the back of the MK2 to help it actually pull it out of the Y splitter enough to let the next one be fed in. Same goes for when it's feeding filament towards the Y splitter, the MK2 is spinning at times but there's nothing moving, and you can hear the gears just grinding against the filament. It seems like the more I try and solve this, the worse it gets (-_-); I'm just...kinda getting over trying to get this to work, honestly. I'm sure in a year or so 4 color (or more) printers will be fairly affordable. That said, I know I just listed a myriad of problems, but I'm really not expecting much as this point. If you have any suggestions for the extruder gears on the MK2, I would be willing to give that a shot at least. That seems to be the biggest issue right now.

Well, I've been trying to get a print to work, and I run into the same issue every time. Anytime there's a filament trying to be moved by the MK2 extruder and it has been formed at the end by the hotend through the custom gcode, the end of that filament has a rough time making it through the bowden tube provided with the kit, and even sometimes gets stuck in the Y splitter itself. I have tried printing with the hot end at 200 and 210, both with the same issue, if that matters at all. I have a spare piece of Capricorn tubing and some of the tubing given with the MK2, as well as one of the formed ends of the filament made by the custom gcode. This formed end slides pretty well into the Capricorn, but definitely meets a fair amount of resistance going into the tubing given with the MK2. I would say I could just replace the tubing with something better, but that doesn't help with these tips getting stuck in the Y splitter. Is there a tweak of some kind I can make to the gcode to make these formed tips a little nicer? I notice that while a tip is formed pretty well, there is still a noticeable bulge in thickness for 6 or so millimeters on the end there (1.9 mm thick, according to my calipers). So the only way to get a print to work now is to babysit the entire print and manually feed or unfeed any filament between color swaps myself if the MK2 is unable to do so alone. And even then, sometimes the filament gets so stuck that I can't even move the filament to where its supposed to be in time to prevent 2 of the filaments colliding into each other in the Y splitter. (and yes, I make sure the current tool selection isn't on the one I'm trying to feed by hand, to make it as easy as possible)

1) Oh, by single or dual connector I meant either there's a a bowden tube connected to just one side, or both sides, of the extruder, respectively. I think I found a printable mount that'll move the extruder over enough to eliminate the issue altogether. 2) RIP Cura... (for more than 2 colors, anyways lol) 3) Ok, I was pretty close to that, was feeding them up to just inside the start of the Y splitter. Thanks for the quick response! Once I reattach my extruder with this mount, I'm gonna give my first 4-color print a shot!