Changes disappeared from store front

Sorry if the question is daft. I'm only crawling through early stages of OC.
Using OC Europe 1.5.4
Admin language - english

Ive been going through categories, modules and layouts checking progress on the store front when for unbeknown reason everything disappeared there.
What the heck have I done and what file is missing? (favicon seems in place). I dont really want to go back to the beginning (not yet), just trying to understand whats going on and how to avoid stupid mistakes.

Thanks in advance for you patience.
Error logs
[Tue Feb 05 15:19:36 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/404.shtml
[Tue Feb 05 15:19:36 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/favicon.ico
[Tue Feb 05 15:18:30 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/404.shtml
[Tue Feb 05 15:18:30 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/favicon.ico
[Tue Feb 05 15:18:16 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/404.shtml
[Tue Feb 05 15:18:16 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/favicon.ico
[Tue Feb 05 15:18:10 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/404.shtml
[Tue Feb 05 15:18:10 2013] [error] [client 31.51.218.89] File does not exist: /home2/bebemira/public_html/favicon.ico
[Tue Feb 05 12:37:48 2013] [error] [client 178.154.243.95] File does not exist: /home2/bebemira/public_html/404.shtml
[Tue Feb 05 12:37:48 2013] [error] [client 178.154.243.95] File does not exist: /home2/bebemira/public_html/robots.txt
[Tue Feb 05 12:03:12 2013] [error] [client 157.55.33.111] File does not exist: /home2/bebemira/public_html/404.shtml
[Tue Feb 05 12:03:12 2013] [error] [client 157.55.33.111] File does not exist: /home2/bebemira/public_html/robots.txt