Chris Wilkinson, who heads the firm and studied his profession in Liverpool, designed the Millennium Bridge across the Tyne in Gateshead and was awarded the Royal Institute of British Architects Stirling Award two years in succession.
He said: "We can't understand why they have focused on this. We have had a very positive meeting and letter from CABE. There's always some points of concern, but they are minor points.
"Some of the scheme they haven't fully understood because they only had an hour to look at it.
"The reason we have designed such a big open space is because there's the opportunity to have large open events. The whole point is that it has to have outdoor facilities.
"We have got some residential plans around the car park, but it's a tiny proportion of the whole scheme.
"We have taken on board the comment that they have made.
"It's a fantastic design and it's had a very positive response from the public. In the four-page report they (CABE) sent us, it had a glowing response."
Jim Gill, chief executive of regeneration body Liverpool Vision, which is behind the plans, said: "CABE's conclusion on the proposed scheme is positive.
"Their comments on individual elements will be taken into account and addressed as the detailed design is progressed."
Cllr Kiron Reid, assistant to Liverpool council leader Mike Storey, said last night: "CABE is a well-respected organisation and we should listen to them carefully.
"The city needs good quality design but we can't do that without looking at cost as well. We need to take both into consideration for the Kings Dock scheme."