I've just migrated from 6.52 to 8 and i didn't found the CDF OpenForm and FormOpenRelated already present in DFW. Why?

I used this function in 6.52 in many OMLs and in many databases. Please see  an example below.

I've simply add this function with the correct dll to the custom function table in DE8?

Why they are removed?

Example   

define "a" number .
if count of TamvTamtNECLAIMS > 0 then
a := FormOpenRelated ("TamvTamtNECLAIMS , TamtVTopCustCheckUpd") .
else
message "Nessuna valutazione ancora da valutare per i CLAIMS" window .
end .

In 6.x there was developed a library called DFWACTS.DLL i.e. DataEase Actions as CDFs.

In 7.x these functions was included in the core product and no longer need to be defined as CDFs.

As a result of this every script/derivation that use these functions need to be rebuilt/recompiled as the function number internally is now different even though the syntax etc. is the same.