Addition of custom tab and fields in cProject

Hello Experts,

I need to add custom tab and fields in cProject project definition level(type DPO).

As it is given in IMG help, there are two ways of doing this.

1) Addition of data in CI_DPR_PROJECT and Creating the field groups and including these fields in the field groups.

2) Creating the custom tab and assigning the webDynpro component to it.

I tried the first method. Here I am able to see the field group as the tab in cProjects but the fields included in CI_DPR_PROJECT are not appearing.

Please let me know how I can see the fields which are added to CI include.

Also,

For the second method what is the meaning of implementing the WebDynpro interface DPR_CUST_EXT_INTF ?

I appreciate if anyone explains step by step procedure for this.

Thanks in advance.

Regards

Maddy