Appearing Custom field inputs in MIRO item level (BAdI mrm_item_custfields)

Hi Experts,

I apologize if I have not followed other thread helps and the question is repeated. 

I followed the below thread to implement the custom tab in the MIRO item level except I left or not done the append fields to RSEG table. Remaining of all the steps provided in the link are covered. 

https://www.sapyard.com/steps-to-add-custom-tab-in-standard-miro-item-screen-using-badi-mrm_item_custfields/

Other than my screen inputs all other values are appearing (in t_drseg_custom TYPE tdrseg_cust ). I can see my fields are there in the debugging screen but values are not passed. 

Please help me  where did I miss and how to fix this? Many thanks. 

Note:

The reason I left the RSEG part , I have a different requirement where I have to use the Fiori custom fields, which are already created in RSEG, that are to used to for saving the values. A different thread (Q&A) has been posted and waiting for response/answers. 

https://community.sap.com/t5/enterprise-resource-planning-q-a/miro-badi-using-calling-fiori-custom-fields-in-drseg-ci-and-ci-drseg-cust/qaq-p/13742454

I would be grateful if anyone address to the above as well.

Thanks for your time here.