@Wen Chien Hsu,
I just checked your site and found the reason of the issue. You were using the old version of WP ERP. I just updated WP ERP and “Custom Field Builder” extension is working perfectly now.
And about the view of Company basic information:-
Right now, it is due to the default feature of WP ERP. We will make some changes in future releases to show more information in the CRM/Company page.