Well you can always get the files from BYOP. I dont have them publicy for download because of the fact I did not want people e-mailing me saying DPB wont work.
Atlantis is possible to use right off the bat. Just edit a couple entity's around if you would like. Textures we compiled with the map. I used this map on one of my old servers rotation.
But as far as Jungle map goes. The map is still looking for the Half-life wad located within the Sierra folder. (That was the WON days for n00blets reading this...) Your best bet is to decompile the map, figure out the missing textures used....then use a good copy of the map. And compile the textures into the map yourself. It's very doable, will take a hour or so of your time.
I had copies of working Beta 1 maps on my old 2.1 server 5 years back. But i missed a payment and forgot to back up the maps before i lost those. Or I could have really helped your situation.