Upgraded to Xubuntu 7.10. In default 1280x800 resolution, all fine.
Allegro now does switch mode back on shutdown, but there is a new problem: changing the screen resolution to 640x480 or 800x600, whether in Allegro or in Xfce settings at the default refresh rate, turns the screen into an unreadable mess of flickering near-horizontal stripes. These modes do work in Xfce if the refresh rate is set manually.
Upgraded to Xubuntu 7.10. In default 1280x800 resolution, all fine.
Allegro now does switch mode back on shutdown, but there is a new problem: changing the screen resolution to 640x480 or 800x600, whether in Allegro or in Xfce settings at the default refresh rate, turns the screen into an unreadable mess of flickering near-horizontal stripes. These modes do work in Xfce if the refresh rate is set manually.