adding device description files is a two step process.
first devices are installed on your system. then they are added into local catalog of specific application.
if the devices are already installed on your system (by WorkVisual or some other program for example some PLC programming software) then they will be searchable by any application that can use them.
in case of workvisual, after search, left pane shows all devices that are installed on your system.
right pane shows list of devices presently in the DTM catalog. this is shown by labels directly above the panes.
you can use four arrow buttons to add or remove description files from WorkVisual DTM catalog. unfortunately WorkVisual still does not offer feature to remove description file from the system after it is no longer part of the DTM catalog.
the issue here is that each software uses own catalog.
so if you want to add ABC.GSD, it will be installed on your system. then reference to that will be added to catalog of specific product (such as WorkVisual, Step7, CX programmer etc.).
When you do a search, you may find many other devices that were installed by those other programs.
Removing device from catalog of specific product (such as WorkVisual) does not guarantee that the same ABC.GSD is no longer referenced by those other software products (such as CX programmer).
Removing ABC.GSD completely using one piece of software (WorkVisual for example - if it could do that) would lead to corruption or missing entries among those other software products.
And since each of them has own (and proprietary) catalog, it is not likely that foreign tool or application will be able to neatly remove it from every catalog that may be on your system...
ok, so this must be managed by KUKA itself , but for now , they don't care about this functionality 
