As of 1.4.x and later when run under a desktop with appindicator support such as enlightenment nm-applet exits with (0) almost immediately with no error messages or warnings printed.

Some initial printf debugging shows that nma_init() is called however applet_startup() is not which leads me to think that the startup signal isn't called. On a desktop that still supports xembed such as IceWM it functions as normal. I'm happy to help but not that familiar with gtk so i'm not sure where the best place to look is.

Tested with nm-applet 1.4.0, 1.4.2 and git master on openSUSE Tumbleweed

static void nma_init (NMApplet *applet)
{
	printf ("nma_init\n");
	applet->icon_size = 16;

	g_signal_connect (applet, "startup", G_CALLBACK (applet_startup), NULL);
	g_signal_connect (applet, "activate", G_CALLBACK (applet_activate), NULL);
}