The names are GUIDs created by the editor for each file. If you save them with the editor again, your engine will not recognise them.
The easy way is to keep them in the cache folder and just set the PurgeCacheDays variable to a high number. The problem is that you cannot play these maps offline with bots (or can you?)
That's what I do; it works fine:
Just write down the name and size of the file while downloading as well as the current time. After playing move the files to the appropriate folders (maps, textures, etc.) and rename them using the size and time to identify them.
Mostly, there are two types of files you download: Maps and Textures. You recognise maps by the charateristic prefix (e.g. DM or INF_). Those have to renamed by the name you've written down (check the sizes as well) plus the .unr suffix. Move them to the maps folder.
Most Texture-files, however, just get silly names by their authors (gamer:=hacker; just a joke!!!
, so you have to guess, if it really is a texture file and not a sound file etc. You have to rename them to .utx and move them to the textures folder.
Six.
[This message has been edited by Six (edited 08-12-1999).]