Sys_Error: _default material not found

[s]

Anyone run into the error Sys_Error: _default material not found when trying 
to run Prey and know what's wrong? 

more of the error:

file system initialized.
--------------------------------------
----- Initializing Decls -----
------------------------------
------- Initializing renderSystem --------
idRenderSystem::Shutdown()
Sys_Error: _default material not found

I figured either the download or copied files are bad, but I've redownloaded 
both and it didn't help.  Anyone have the md5sum of the Prey binaries 
download? 

Thanks in advance.