Hello once again,
after fixing the alignment problem, my compilation now fails
a couple of pages later: luatex crashes with SIGFPE when trying
to write a PK font.
I do not have a simple test case yet, but I think I see the problem
in the source: in source/texk/web2c/luatexdir/font/writet3.w, function
writepk(), one call to pdf_printf() divides by newdpi, which can be
zero when pk_fixed_dpi is not set.
What is the intention behind dpi vs. newdpi?