Characteristic relationships and input layout

Dear Experts,

I have an input layout on a planning infocube. By saving new data in the layout I want to start a characteristic relationship and derive some characteristics. In the theory to be executed the characteristic relationship should get all the source characteristics filled with values. I have 2 source characteristics and one of them is # in some cases. When char2=# my Characteristic relation does not start. Is there a trick to start it for the combination char1 = value 1 and char2=#?

This happens only when I am using layout. When I execute copy function for example and the data in some rows is exactly the same char1 = value 1 and char2=# the characteristic relationship starts and derives value for the target characteristic.

We are on BW on HANA system.

thanks,

Maria