Go to this site using the link and do a search for "hlbasics" in the downloads search box at the top of the page. They have a ton of dod 1.3 files as well as many hundreds of CS 1.6 files. I run a cs 1.6 server on dod maps with a capture the flag plugin, So i know what your trying to do. good luck its a lot of work to get the server just perfect.
hlbasics
Bye the way you can always use GFscape.exe to extract dod files from the game cache if you have dod installed. If your going to be doing a lot of maps and you own dod, Then it would be worth it to install it in order to save time.
__________________
{FJ}Justice STEAM_0:0:633975 If anyone needs any help with their server, Just add me to steam friends and I'll help you out.