Thanks for the showcase, and the information about 1.0.18 version number.
I suppose that the Lite version from WordPress.org is installed and overwrite the Pro version, that is why the tabs that is supported in PRO version are disappeared.
We have made a new 1.0.21 version, in which the plugin directory, the mail plugin filename and plugin name are renamed, containing the “pro” postfix.
This prevents that the pro plugin is overwritten by the lite version.
Please delete your whole WooCommerce Custom Tab plugin directory, and install the new one.
It can be downloaded from My Account menu of webshoplogic.com site.
The name of the download file is “woocommerce-custom-tabs_pro_v1_0_21_PR.zip”
I hope this solve the problem.