how to set the baseurl to point to a dir other than /ckfinde

Do not move ckfinder.html anywhere. Here's the mistake:

_FileBrowser.BasePath = "/Images/";

_FileBrowser.BasePath should point to your CKFinder directory, i.e.:

_FileBrowser.BasePath = "/ckfinder/";

URL and server path to the Images directory may be set only in config.XXX file.

For example in CKFinder for PHP, edit config.php and set the right $baseUrl:

$baseUrl = '/images/'; 

(I assume that this helper variable is used later in configuration file)