Here are the instructions to get that thing to work :

-Put Tiles020.ART and Tiles021.ART in your Duke folder

-Put the beerz and kaiser folders in the highres folder of your eDuke or JFDuke install.

-Put the sky_alien and sky_sea folders in your highres/skyboxes folder (Note : if you got KaiseR Land 1 you should already have a sky_sea folder. Its content is a skybox for tile 94 / palette 0. Here is the skybox with palette 1. The name is different, so that both skyboxes can coexist)

-Write this in your skyboxes.def file :

// sea sky / midday (94)
defineskybox 94 1 0 highres/skyboxes/sky_sea/94_1-front.jpg highres/skyboxes/sky_sea/94_1-right.jpg highres/skyboxes/sky_sea/94_1-back.jpg highres/skyboxes/sky_sea/94_1-left.jpg highres/skyboxes/sky_sea/94_1-top.jpg highres/skyboxes/sky_sea/94_1-bottom.jpg

// alien sky (1100)
defineskybox 1100 0 0 highres/skyboxes/sky_alien/alien-front.jpg highres/skyboxes/sky_alien/alien-right.jpg highres/skyboxes/sky_alien/alien-back.jpg highres/skyboxes/sky_alien/alien-left.jpg highres/skyboxes/sky_alien/alien-top.jpg highres/skyboxes/sky_alien/alien-bottom.jpg

-Put kaiser.def and beerz.def in your highres folder

-Write this in duke3d.def :

include highres/kaiser.def
include highres/beerz.def

Now fire up the game and blast some ugly alien ass !