Hello mf_galberico:
It should work the same, possibly depending on the contents of the file "flsetl.PRO".
I recommend that you create a zip archive containing just the three files flsetl.PRO, flsetl.SRT, and flsetl-CRE.dat, then open a support incident to represent this problem through your account at supportline.microfocus.com, and attach the zip archive to the support incident. Or attach each of the three files individually. Then we could try the same experiment on machines at Micro Focus, comparing the behavior of dfconv between Server 5.1 with Server 2.3.1.