Thanks for your post,
You need to go Category Field Set menu and expand the categories you want to hide phone number, uncheck the checkbox, please see the attachment.
from this menu you can hide/display input field for specific categories.
View post on imgur.com
Regards
Also please check the link for language files
https://plugins.svn.wordpress.org/classified-maker/trunk/languages/
if you want to contribute please translate these file for your languages and send us via http://pickplugins.com/contact/
Regards
