When I load a read-only document, most editing controls are grayed out, which is fine. I can still print or "save as", as expected.
When lyx-1.4cvs starts for the first time it loads splash.lyx, but forgets to enable those few buttons that work for a read-only document. (I.e. everything is still grayed out, the way it is when lyx is running with no documents at all.)
This isn't important for functionality, but could possibly give first-timers a bad impression if they want to print to see the fabulous typesetting quality. :-)
Helge Hafting