Mathod for flexible upload od master data

Hi

In our scenario before user upload reported fin. data he must create new values for some subassignment.

I want to give end-user posibility to create the new values for subassignment in UCMON.

For this purpose I consider to use Flexible upload, but I can't create method for collecting the master data!

Is there any possibilty to create master data from UCMON?

Thanks for any suggestions 😉

regards

Pawel