Much of the world watched the opening ceremonies at the Winter Olympics in Sochi, Russia, on Friday, with few with as keen an interest and an expert eye as special event professionals. Here are their takes on what worked well and what did not:

A 'WOW' TECHNICALLY Overall, event pros give high praise to the technical expertise demonstrated in Sochi, especially the use of projection mapping.

"The technical skill was second to none," says Doc Waldrop, head of Full Circle Lighting and Productions of Atlanta. "The projection mapping was breathtaking, and the content provided for the projectors was very well done."

The highlights: "The water scene with the boat was spectacular," Waldrop says. "The story of St. Petersburg was also very well done, with the map spinning to another locale as the marchers moved. I'm still trying to figure out how the cannons worked when they fired ... " On a scale of 1 to 10 with 10 being best, "I would give them a solid 8.5," he says.

"Projecting the world map onto the ground looked beautiful, and flying the large set pieces through the air was very unique and fresh," agrees Jon Adcock, president of Orlando, Fla.-based PTE Productions. "I also enjoyed subtle elements like the LEDs installed into the side of the seats and down the walkways with the ability to control them and add them into the show. It's always great when lighting radiates from the audience and not only from the stage.”

"Nothing can top what Beijing did in the Bird’s Nest[in 2008]--with tens of millions worth of LED panels--but at Sochi the backgrounds projected on the floor seemed to integrate well and support the storyline," notes David Corwin, head of Megavision Arts in Santa Monica, Calif. "I heard there were issues with viewing some of the scenes 'upside down' from the non-media side of the stadium, but that’s always an issue with theater-in-the-round-style seating."

FAILING SNOW Debbie Meyers-Shock, CSEP, head of Dallas-based Bravo! Entertainment, says she "hated" to see the snowflake fail to morph into the fifth Olympic ring. "No one, I hope, likes to see technology fail at any event," she says. What most impressed her: "The amazing and colossal rigging system, and the projections on the stadium floor. I understand there were 120 projectors and brand-new software that made it possible. I love seeing new ways to use event technology."

She adds, "The visual moment for me was the sailing ships depicted as video etchings with the human interaction. The illusion that they were working on a real ship deck was incredible."

Waldrop says he feels sympathy for the Sochi team after the snowflake fail. "I was a bit disappointed to see on social media that a fair amount of industry folks jumped on the fact that one ring failed to function properly," he explains. "My heart sank for the production team at that moment. I daresay that no one that tries to put on an event of this scale and of this magnitude is immune from a mechanical failure, or an unfortunate mistake."