I am using Plain TeX to write my (scientific) texts which usually include many awful equations and graphs (or figures) I am constructing with unsurpassed PicTeX. My big problem is that with my MikTeX version I cannot input more than two
\input pictex in one Plain TeX file (at the third pictex call the file cannot be texified and blows out). So I have to write a separate file for each extra graph above two, to output their pdf file, and to merge at the end all the pdf with the defect that the extra figure files are at the end of the text (and not in the body of the text as for usual texbooks).
Is there a way to set TeX parameters so that more than two pictex calls can be made in one Plain TeX file? Thanks for solution (If you insist that I have to run LaTeX, I am not really a big fan because LaTeX is relatively limited).