The early pre-release screenings of the movie were disastrous. The percentage of the audience who liked the movie fell into the mid-30s, and executive producer Mario Kassar realized the main problem was that the plot made zero sense. His solution: have the Ra character's dialogue subtitled, and made into information that presented a clear storyline. When these changes were made, the subsequent test screenings produced an overwhelming majority of positive reviews, and this carried the movie into becoming one of the surprise hits of fall 1994.
Jaye Davidson thought his performance was terrible, and did not know that his voice would be altered (which was an afterthought during post production) or that he would otherwise be made to appear any more alien. After the first screening of the film, Dean Devlin found Davidson in tears. When Devlin attempted to apologize, Davidson responded "no, you saved me", and thanked him.
Ra's glowing-eye effect was added in post-production, because test audiences didn't think that he was alien enough. This trait was continued in Stargate SG-1 (1997), as an identifier to people who are taken over by the Goa'uld.
Jaye Davidson's dislike of the attention that he received after The Crying Game (1992) made him reluctant to take the role of Ra in this film. He didn't want to just turn the offer down, so he made what he expected to be an unacceptable demand of $1 million. This was accepted, and he appeared.
James Spader admitted that he did the film for the money, as he found the script to be awful. He said, "Acting, for me, is a passion, but it's also a job, and I've always approached it as such. I have a certain manual-laborist view of acting. There's no shame in taking a film because you need some f****** money."
Roland Emmerich: [rain] (at around 6 mins) Roland Emmerich says in the commentary he loves rain and includes it in all his pictures.