Something went wrong, read below to solve it

It seems as if you have not correctly done the URL so the loading screen would work. Have you read the guide? I take it you have not! Please choose one of the following options

Either you can test the loading screen with my steamID. This will make sure that your loadings screen is configured correctly.
But do note that server name, server map and server gamemode will not be shown as that is shown when the user is loading with javascript: http://swiatszynszyli33.5v.pl/?steamid=76561198051229287

If you instead want to get the link to put in your server.cfg, then choose this link. The %s is the steamID of the connecting user and ?steamid is the function to fetch this steamID: http://swiatszynszyli33.5v.pl/?steamid=%s

If you got further problems, read the guide and if you still have problem please contact me on Steam.