Hi there
A very small detail, but the two examples given in the admin that show what to enter in .htaccess were not valid for me. I think this is quite common on some installation setups.
For myself, I had to add the full path with sub directories.
"ErrorDocument 404 /shop/friendly_url.php"
Ok, this maybe obvious, but as the admin knows where viart is installed to it should reflect this maybe in the text it shows.