When you install an updated version of an extension, are you uninstalling the previous version from the extension manager first?
If you do not uninstall the previous version first, it can cause the configuration folder to become corrupted, make sure you always uninstall the previous version from the extension manager before installing an update.
The issue with the filecache.dat file having to be deleted is due to an Dreamweaver bug. That file is supposed to be deleted automatically if there is a problem. However a bug in Dreamweaver is preventing that from happening. The fix of deleting the filecache.dat file is the fix recommended by Adobe.