problem solved.

[derek]

By dint of much hanging around #clanlib I've learned that:
My ancient video card doesn't allow textures larger than 1024.
CL_Sprite (vs CL_Surface) tries to create a texture that won't fit.

use-opengl in globals.cxx was defaulting to true, and was being set to true 
with -G, thus
SDL was never being used.
As soon as I switched to SetupSDL::init in pingus_main.cxx, everything worked 
fine.

grumbel and Judas- think the 1024 and 1023 memory growth issue is unrelated.
Possibly an off-by-one error somewhere.