devfiles contains the configurations that RME uses. However, the subdirectories under this directory are indexed by DCR ID, and are not easily searchable. The shadow directory is designed for external use.
As for backups DO NOT just backup the devfiles directory. This will be useless to you without the associated rmeng database. Instead, use the CiscoWorks backup feature to backup the whole suite, then archive the resulting backup directory. In this way, you can be sure that if a problem occurs, you will be able to bring the entire product back up.
As for the shadow directory, you are free to archive this directory any way you'd like. RME does not make use of the configuration files therein. If you are missing entries in this directory, I suggest you upgrade to LMS 2.6 which includes RME 4.0.5. This release has a new feature that will ensure a more complete shadow directory.
