The Hollywood star signed on in 2019 to appear as Kate Jones in A Patriot, a dystopian thriller where she would be paid a $1 million (£830,000) fee.
Green has sued in the High Court in London for her unpaid fee, but faces a counterclaim that she deliberately wrecked the project by walking out on production.
Giving evidence, the film’s writer and director Dan Pringle said Green’s fee ended up hampering efforts to get the film made, and she made a series of “unrealistic” suggestions about crew that could be hired.
“I didn’t know her well enough to know how serious she was being with some of her suggestions”, he said, referring to some as “crazy” and “Hail Marys”.
Mr Pringle said Green suggested they could approach Dark Knight director Christopher Nolan’s director of photography, and would say in meetings they should “reach for the stars”.
“It was not realistic, then we would move on to another potential target”, he said.
But the actress had a scheduling clash with filming for TV series The Luminaries and a funding deal with Sky was lost.
Mr Pringle, a relative directing novice, said Green “had her own high standards” which “was the cause of a certain amount of frustration for all of us”.
“I think it is fair to say that Eva was at times a little unrealistic about some of her suggestions of heads of department or key crew because the individuals were either too high-profile and/or too expensive for an independent production of our kind with a second-time director making a significant leap up”, he said.
“Her desire to try to secure the very best individuals available only demonstrated to me that Eva took seriously the commitment she, Adam (producer Adam Merrifield) and I had made at the outset to try to make the very best film we possibly could.
“Eva’s name brought opportunities which would not have been available to Adam and I and the worst that could happen was that the candidate said ‘No, thank you’.
“Ultimately, I think Eva’s choices of those key crew that we were able to secure demonstrated that she was prepared to approve realistic candidates that the production could afford, in line with the financial resources we had available whilst we were planning to shoot in Ireland.”
In the troubled production, plans to film in Ireland were abandoned over funding difficulties which left Green “very upset”, said Mr Pringle.
But he said she offered to work without a trailer and stay in local hotels to save money, in order to “shoot as much of the film as possible on location”.
“I understand this is now being held out as an example of Eva making unreasonable demands, but I do not share that view”, he added.
Green says she has been unfairly “painted as a diva” in the legal battle with financial backers White Lantern and executive producers Jake Seal and Terry Bird.
She says Mr Seal was parachuted into the project in a desperate bid by financiers to recoup their initial investment, and he was instrumental in efforts to reduce the film to a “cheap B movie”.
Mr Pringle said he was told to focus on the creative elements of the film rather than finance, but he was aware of troubles as the planned $10 million budget was reduced to as low as 5.3 million euros.
The court heard extracts from a discussion between Mr Seal and Mr Pringle over Green’s fee, in which Mr Seal said the actress was “overpaid” for the film.
Mr Pringle said the star “acknowledges” the position, and Mr Seal then says: “Her name is not that value.”
“The nature of having to get a bridging loan to secure her fee – it became clear to her that was having an impact on the project”, said Mr Pringle in his evidence.
He said eventually they were in default on the loan and “racking up interest by the week”.
Green, the star of Bond film Casino Royale and Disney’s Dumbo, is expected to be questioned on Monday, including on the contents of texts where she branded Mr Seal as “evil” and a “mad man”, referred to herself as “Cruella”, and called crew members in Hampshire “shitty peasants”.
Green is up against White Lantern Film (Britannica) Limited and a second defendant, SMC Specialty Finance LLC.
The trial continues.