The architects responsible for the 45-story Westin Hotel in Times Square have been quietly working on plans for a new Coney Island.

The flashy Miami-based firm Arquitectonica said yesterday that since March it has been working with the city’s Coney Island Development Corporation on plans to restore the area surrounding the storied but relatively rundown amusement park. The project stretches roughly from Surf Avenue to the boardwalk, all the way from the Brooklyn Aquarium to 24th Street.

The crown jewel of the area, the corner of Stillwell and Surf avenues, is being simultaneously developed by Thor Equities and designed by architects at Ehrenkrantz Eckstut and Kuhn. A spokesman for EEK and Thor Equities, Lee Silberstein, said yesterday that the developer is collaborating with the city on the site.

A recent error on the architectural firm’s Web site, however, illustrated a lack of communication among the various parties involved in the redevelopment project.

EEK recently posted a preliminary rendering for the 10-acre site on showing that a residential high-rise, a luxury hotel, and a new pier, complete with a new ferris wheel, have been proposed during the planning process.

Mr. Silberstein said yesterday that the renderings were “inaccurate” and that they had been posted “erroneously.”

He called the posting of the proposal “unauthorized,” saying that it “was not accepted by Thor.”

He added that an updated proposal for the site may be released in about three weeks.

Arquitectonica would not comment on its vision for the surrounding area, directing all inquiries to the Department of City Planning.

EEK’s renderings for the Stillwell site, since removed from the firm’s Web site, show the lot from several different perspectives, offering some clues about what the condo high-rise and the luxury hotel that the developers have discussed may look like.

The rendering places a massive entertainment complex there, including a movie theater, dense signage, an indoor waterpark, and scattered concession booths shaped like Coney’s storied Parachute Jump. A plaza would be enclosed by two tall beachside buildings, which would presumably house the condominium apartments and the 500-room hotel that the New York Times has reported that Thor Equities is considering.

Mr. Silberstein said the corner has been allowed to deteriorate over time, and that whatever ends up going there will “enliven” it.

The EEK renderings were labeled “conceptual” plans and dated to June. A caption called the site “a mixed-use entertainment complex which will include residential, hotel, retail and a new waterpark.”

The caption also noted that the redevelopment “fits into the master plan as developed by the Coney Island Development Corporation.”

The director of public affairs for the CIDC, Andrew Brent, said the city had not seen the renderings.

“While we have not seen their specific renderings, we are encouraged that Thor Equities is looking to bring private investment to the area,” Mr. Brent told The New York Sun in an e-mailed statement. “At the same time, we are also working to ensure that the goals of the City’s strategic plan and the interests of the community are a priority as we move through the rezoning process, and we will work with any private investor including Thor to ensure that a balance is met.”

Mr. Brent did not specify when a final plan for the site would be announced, and the CIDC’s Web site does not provide a schedule for upcoming board meetings.

EEK’s renderings were first linked and discussed on the Wired New York online forum, where Brooklynites anonymously but vehemently criticized the plan.