Hello,
I've written about this elsewhere (http://www.concrete5.org/community/forums/customizing_c5/theme-wont... ), but no luck - maybe it wasn't the right forum...
So, again:
1. I installed C5 on a subfolder on my server. The domain of my site (kiedybylammala.art.pl) was redirecting to another subfolder, one with the previous version of the site. Installed my custom theme. Everything worked well.
2. When all the content was set, I changed the subfolder my domain was pointing to so that it was redirecting to the subfolder containing my C5 installation.
3. C5 stopped displaying my site. Only a blank page with the C5 logo and the message "File /concrete/themes/kiedybylammala/default.php not found. All themes need default.php and view.php files in them. Consult concrete5 documentation on how to create these files."
4. The site cannot be viewed athttp://www.kiedybylammala.art.pl - but it still can be accessed if I try the path to the subfolder where it resides (www.www.manufaktura.art.pl/kiedybylammala_c5/)....
5. The dashboard and all the administrative interface can be accessed throughwww.www.kiedybylammala.art.pl/index.php/dashboard.... Everything related to the theme, though - like editing the pages - is impossible to do.

I have no PHP or MySQL knowledge, but to me it looks as if C5 has a path to the /themes folder that is written somewhere (in the database?). As the domain was changed, this path wasn't - C5 stopped "seeing" the /themes folder an thus, started looking for the theme in the /concrete/themes/ folder, and didn't find it.

But what should I do to make it work at last? Where do I have to look?
Please help me, somebody... :-)

Thanks in advance,

Mikołaj Kamler