Generic Extraction - FM - delta enabling

Hi experts,

We have a requirement for a report to develop in BW. The fields required for this transaction data report are from different tables ( all from SD) i.e, some from Standard Tables and few from Customized. Out of 20 fields to derive, each field has different logic (like loops and Read from multiple Tables).

So we have Choose to create generic DS with FM based.

Now the issue lies while writing the FM code in Enabling the Delta. My Custom tables has a Date Field or Time field but whereas Few Standard tables do not have created or Changed Date Field (eg: VBPA).

Question 1: If i use time stamp delta, i do not have a Time stamp field in any of the SD tables (both Standard & Customized). Can i create a Dummy field like TMSTMP (time stamp) in my structure and use the same to extract Delta records ? will it work ? If so, will it capture data for all the changed fields ?

Question 2: Can we use 0Calday.. Since few of the standard tables do not have Date Field, so if that table gets updated with new/changed records, will this delta Capture those ? Or can u please suggest any way on how to extract data in this case ??

Or any other alternative solution for my requirement within functional Module..

Awaiting for your valuable inputs !!!

Thanks,

Radhika