Autodesk Architectural Desktop provides a way to make certain the Layer Key Style in your drawing files reflects the latest revisions without having to manually import the revised Layer Key Style [or even to know that it has been updated]. The image and procedures shown here were created/developed for ADT 2004, but the same feature is available in later releases.
The Layering tab of the Drawing Setup dialog allows you to specify a Layer Standards/Key File to Auto-Import. If you have not done so already, you will want to establish a file to hold your Layer Standard[s] and Layer Key Style[s]. The AecLayerStd.dwg file holds the out-of-the-box Layer Standards and Layer Key Styles. For the 2004 release, on a standalone, local machine installation, this file is located at:
C:\Documents and Settings\All Users\Application Data\Autodesk\Autodesk Architectural Desktop 2004\R16.0\enu\Layers
The path will be similar, with some minor variation in later releases. If you have a customized installation, particularly if some files were placed on the network for common access by all users, this file could be anywhere, but is likely located with your other content files.
If you have customized or plan to customize either the Layer Standard or the Layer Key Style[s], I would highly recommend starting with a copy of the AecLayerStd.dwg file, renamed to reflect that it has your firm's customizations, to make migration to new releases easier. Be certain to back up any customizations, whether to the AecLayerStd.dwg file or your own custom file.
Having identified the name and location of your central source file for Layer Standards and Layer Key Styles, you will want to make that your Auto-Import file by selecting the ellipsis [...] button to the right of the Layer Standards/Key File to Auto-Import area, navigating to your file and selecting it.
Next, set the Layer Key Style from your source file that you wish to be current, using the dropdown list in the Default Layer Standard area. Then note the toggle at the bottom of that area, labeled "Always import Layer Key Style when first used in drawing". Check that toggle if you wish to automatically update your drawing file with any future changes made to the Layer Key Style in the source file. If you want that to be the default condition for all drawings opened on that computer, for that users, also check the Save As Default toggle in the lower left corner. [You may want to check the settings on the other tabs to be certain they have the desired initial default values set before hitting OK, as the Save As Default toggle affects the entire dialog box.]
Here is how this feature works. The first time you issue an ADT command in a given editing session for that drawing [and any other in which the Always import Layer Key Style when first used in drawing toggle is checked], ADT will check the file specified as the Layer Standards/Key File to Auto-Import to see if the Layer Key Style has been edited and saved more recently than the current drawing file. If so, it will automatically import the Layer Key Style from the source file before making use of the referenced Layer Key. If not, the Layer Key Style in the drawing file will be used. No additional checks on the Layer Key Style will be made during that editing session. If you are told the Layer Key Style has been updated while you are editing a file, you can either use the Style Manager to update it from the source file manually, or save [if you want to keep any unsaved changes], close and reopen the file.
This feature is particularly valuable if you are just implementing ADT and make frequent changes to the Layer Key Style to get things "just right" for your office at the same time others are using ADT for production work.