You may want to post to the blue ridge list. I just checked the sample app and it doesn't work with 1.4, though it gives an error rather than not just running the specs. I tried updating the env.js that blue ridge bundles and that fails in a completely different way ... but, then, so does the 1.3.2 port, so blue ridge needs some sort of update to run with the newest env.js. I can look at the env.js stuff once that happens.
I'm using 1.4 in a non-blue-ridge/non-screw-unit app and haven't run into any incompatibilities yet ... but, then, I also use the Ruby/ SpiderMonkey port of env.js rather than the Rhino version, so that's a difference, too.