Change room slug
There are two constants allows you to change the post type slug of the room post type and the slug of the room_cat taxonomy. By default the post type slug is rooms, and the taxonomy slug is room-type. Resulting in URLs that looks like http://yoursite.com/rooms/room-name and http://yoursite.com/room-type/room-category.
You can change those constants pasting this code in the functions.php file of your child theme:
Please note: you should resave your permalink structure for the changes to fully take effect. Go to WP > Permalinks and click on the "Save" button.