Andrew, a question: you customized the envirnoment variables in question, right? I'm asking because, by checking my own old blog posts (yeah, weird, I know!) I remninded myself that, as of last year, it was no longer necessary to specify the path to the TeX binaries using environment.plist. Instead, you use the "path" option in the build file, which is fully supported. Indeed, I myself haven't used environment.plist ever since.
If you customized other tex-related env variables, the above does not apply to you---the right thing to do is to add the env-injection code to my customized build command. [BTW, the customization is necessary because otherwise you can't properly support error parsing and forward search after compilation, and do so in a cross-platform way]. Again, no ETAs, but I see that this may be a good thing to put back in.
BTW, In the future, please use github to report issues such as these. I don't check the ST2 forums that often, but I get automatic notifications as soon as a new issue is reported on github. Thanks! M