how to downgrade from 2.8.0 to 2.7.x?

2.8.0 pre1 3347-g9d99a30 linux cnc
3.4.9 - RTAI 686-PAE kernel
Debian Wheezy

Installed from with the live cd, somehow got updated to the master release. It's my production machine, and I'm chasing gremlins. Can you please help direct me in the right direction?

Fist thing is to check your repository list and make sure that the one for 2.7-rt is checked and that the one for master-rt is unchecked. Then using synaptic force the version of Linuxcnc to the latest 2.7 version.

If you had a working config before you updated to Master you will need to restore it. Once you have reverted to version 2.7, then you will need to restore your old configuration. Master tries to convert an older config to the new JA system automatically the first time you try to run it. The old config files are saved in a backup directory in the config directory. Restoring those files to their original location should return the config to what it was.