Well I think it should pick up the file (if its in design/<your design>/templates) without the need to specify it in the override.ini.append file.
Did you clear your cache? It is advisable to disabling "ViewCaching" in the [content] section of your site.ini.append.php file (in settings/override, not the original site.ini) while editing templates.
Another thing Bård warned me on: accelerator cache.
When I get "inexplicable" problems, I clear the phpa cache files too (usually in /tmp) and restart the entire apache server+ database with a virgin (empty) var/cache. The latter is mostly taking less than 1 sec, so it's OK.