I have a similar problem but can't figure out how to force my local FRT to keep doing roman numerals right straight through to the beginning of Matthew. It does roman numerals for the title pages, publication data pages, and for the table of contents. But then does latin numerals 1,2,3,4 for the introduction (which is brought in dynamically from INT with \zgetperiph). Then Matthew starts over with pages 1,2,3 AGAIN. I've played with all the various page commands e.g. \dopagenums \nopagenums \resetpagenums -1 and tried different things in ptxprint-mods.tex but to no avail. Interestingly though, if I "hard code" the text of the introduction directly into the local FRT, the page numbers DO behave as expected - i.e. the roman numerals continue through the intro, and then Matthew begins with 1,2,3. But that pretty much defeats the purpose of \zgetperiph.