You might still remember when World of Color had another show stop a couple of weeks ago due to technical problems.
I skimmed throughout Youtube and finally found a video that shows the show being stopped that night.
YouTube - ‪Disneyland's World Of Color Show Cancelled‬‏
Below is a list of the known cancellations/show stops along with any video:
1. Late June 2010: 2nd show cancelled due to a pipe breaking in the viewing area and leaking water. 3rd show went as planned.
YouTube - ‪World of Color Flood‬‏
2. Early July 2010: Earthquakes that hit SoCal prompted the cancellation of all 3 shows. No damage was reported on the platform itself due to earthquake.
YouTube - ‪World of Color Canceled!!!!!!!!!!!!!!!!!!!!!!‬‏
3. Summer 2010: Not really a cancellation. Some unkown problem caused a restart.
YouTube - ‪World of Color Fail‬‏
4. Christmas Day 2010: Audio Problems caused the rest of the show to be cancelled.
YouTube - ‪[HD] Disneyland Christmas 2010 : World of Colors‬‏
5. January 13th, 2011: Technical issues paused the show during Aladdin and was able to continue.
YouTube - ‪1-13-11 World of Color restart‬‏
This means that World of Color has only had 6 known problems that caused either a restart or a cancellation. Happy 1 year in 10 days!