On Saturday the long-awaited new train, the park's only upgrade of the attraction in 21 years, failed to appear after several hours of on-again, off-again operation over the previous two days.
Disney officials attributed the glitches to the attraction's normal "test and adjust" period, when mechanics and designers work out the bugs.
"We are working on solving them," spokeswoman Betsy Sanchez said of the unspecified problems.
She would not predict when the ride would open full time.
It certainly is pretty slick when they were first introduced. I don't remember the last time they introduced new monorail vehicles, but did they had the same lengthy problem as well back then?