Can someone help me read schematics?

Hmmm... call me a fuddy duddy.. but not sure if you should contemplate playing with AC voltages if you aren't comfortable reading schematics... You only have one life and probably like your house not being burnt down ! AC Kills... even professionals... and as someone who fiddles with DC all day, I run scared from AC and recommend all others do the same - it is not to be trifled with. You need to observe some basic precautions, like only ever using one hand (your dominant one), keeping the other hand in your pocket at all times (this is an old 'sparky' trick that will limit (but not eliminate) the ability to have across-your-heart current flow...), triple checking the circuit is cold, and then checking it again... plus a whole heap more...

Setting aside the AC components and moving to the DC ones... its pretty much umm as the schematics suggest...

Maybe you should take a couple of Beers to your local Hackerspace (google for it) and ask them to help you out..

Post a pic of the left carriage... I haven't experienced any issues other than needing to be careful where you position the zip-tie join on the back of the stepper, as it can foul with the RIGHT hand side idler-pulley... but definately no issues on the lefthand motor side..

I'm guessing its actually not the belts.. but rather your cable bundle getting fouled up and blocking the x-axis (doesn't take much to stall the x-axis motor).

I had a similar issue, so fitted the SD3 version of the belt cover on thingiverse.

I could be wrong, but I'm pretty sure if you turn off your motors and move your x-axis by hand all the way left you'll see the cables are whats impeding movement...