Hi Bigus,
1) I'm afraid it is not possible to use your URL with both "/" and without it in default installation; you can either choose to use '' (empty string) as you suffix, so categoires are displayed as directories and articles as files, or '/', then everything is treated as directory;
if you want this functionality, you should add a rule to .htaccess to rewrtie all URLs without '/' to address with '/' or vice versa. But I am not sure, if that would not cause other problems.
2) it is possible if a special extension is added that will load the names from the gallery DB tables and put them to URL
Best regards,
Michal