There are at least four key questions that are unclear in the above summary, that you'd need to answer to know if there is any merit.
1) How were the study subjects selected? In other words, is the sample representative or would it tend to over-represent the homosexual children of homosexual parents?
2) Similarly, was this the primary objective of the study, or is someone extrapolating the alleged results from a tangential study, or is someone conducting a meta-study?
3) Were both parents homosexual (i.e., two lesbians or two gay men) or just one parent? If just one, was the homosexual parent actually out to the child, or did the child find out in adolescence or adulthood? Was it a mixed sampling (i.e., some respondents had a pair of homosexual parents and others had just one)?
4) There are transexual parents mixed into the small sampling, and you rarely, if ever, have two transexuals in a relationship. So, what was the other parent, and also when did the transexual parent change sex (i.e., was it before or after childbirth, perhaps even after the children were grown)?
So, there are really serious problems with evaluating this study from what's reported above, and even from that little it strikes me as a probably misconceived study. Not that this will stop some people from taking it as valid..
I would also like to know which if any of the homosexual parents contributed to the genetic make-up of the child? Which of the lesbians, if any, are the natural mother of the child and which of the male-mo's donated sperm for the child? And if there was a third person involved who donated their genes, is that person gay or straight? In addition, if the child is adopted, what is the sexual orientation of the natural parents? And at what age did the adoption take place? Was the "child" already gay at the time of the adoption?
Cameron really works hard give honest Christian researchers a bad name. This piece is so full of problems that it isn't funny. With his attacks on Dobson and others recently, and his blatantly unethical research practices, he is looking more and more like a self-consumed attention seeker.
What he basically did in this paper is take a few books written by pop authors who interviewed kids and "analyze" the interviews. Interestingly, the author of one of the original books, Abigail Garner, has responded "I had made a point of having a roughly even number of straight kids and second generation [gay, bisexual or transgender – ed.] kids so that both views would be evenly represented in the book. In other words, because of the goals of my book, I deliberately aimed to have 50% of the kids interviewed to be queer. Not because it is statistically reflective of the population, but to give it balance of perspective."
There's a biased, but reasonably coherent critique of this article here:
http://www.boxturtlebulletin.com/Articles/000,012.htm