LinuxQuestions.org - nestra doesn't work on debian (?)

I'm trying out nestra, an NES emulator, on debian squeeze with gnome. When I type:

Code:

nestra game.nes

(where game.nes is a nes rom) I get a small window on screen, but it's empty. When I close the window, I get this at the command line:

Code:

XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":0.0"

      after 1400 requests (1399 known processed) with 0 events remaining.

I can also press escape to get the small window to close. If I do that I get nothing at the command line for output. I've tried two roms. Does anyone know how nestra is supposed to work? I checked the man page, but nothing jumps out at me. Thanks.