> If I set ?registers PO and LL and also set PS and VS, the values of > PO and LL seem to revert to the default values.
As you expected, the order of setting doesn't matter. I don't see anything strange in the run below. where the stderr output follows the closing '!'. groff -ms <<'!' >/dev/null .nr LL 100000u .nr PO 1000u .nr PS 12 .nr VS 10000u .TL Title .tm \n[LL] .tm \n[PO] .tm \n[PS] .tm \n[VS] .LP .tm \n[LL] .tm \n[PO] .tm \n[PS] .tm \n[VS] ! 100000 1000 12 10000 100000 1000 12 10000 .TL and .LP are where all the setup action happens Can you give a short example of what seems to go wrong?