I've been using JBDS 7.1.1 GA with Teiid Designer 8.5.0.Final on Windows and unfortunately I have to say I feel is VERY unstable has any else had issues or noticed anything?
I agree that with Teiid Designer 8.4, but I have not seen many issues with 8.5. So, if you are seeing issues, please enumerate the issues with logs and environment, so that they can be re-produced.
Ramesh..