I did see that mod somewhere, can't remember if it was in this thread or not?
Since you brought up the Y axis.
When you did the ball nut mount on the Y, did you put both nuts on one side of the mounting block (like toward the front of center) or on both sides of center? Talking about the mount to the table, not the table itself.
I ask because I didn't look close enough at mine yet to figure it out and thought I'd ask so I don't have to guess and waste time with something that might not work.