Microsoft has released three free downloadable add-ons for Windows Vista Ultimate, the first time in five months that the company has refreshed its 'Ultimate Extras', once a chief selling point for the operating system's highest-priced edition.

The add-ons include a puzzle game, dubbed 'Tinkers'; a Windows sound scheme based on the game; and new content for Dreamscape, a video-based screensaver.

User reaction on Microsoft's own Vista support forum was lukewarm. "I downloaded them, installed them, viewed them, and will [be] un-installing them," said a user identified as BChat.

"Yes, they are a little disappointing," echoed another Vista Ultimate user, John Barnett, on the same thread.

Microsoft has faced criticism over Ultimate Extras for more than a year. In June 2007, for example, bloggers such as Long Zheng, who writes iStartedSomething, and Josh Phillips, author of WindowsConnected, blasted the company for releasing only a small handful of the add-ons since Vista's debut in January of that year.

Last September, when Microsoft shipped one extra, apparently in response to the increasing complaints, it said it had no intention of dropping the feature.

When Microsoft launched Vista, it touted Extras as one of the main features that separated the the high-end operating system from Vista Home Premium.

The new add-ons can be downloaded only by Vista Ultimate users, who can find them on the Windows Update screen.