Just tried the whole exercise again (yes, all of it), but this time
installing MikteX 'for only me'. I did this to avoid any weird
permissions errors between 'user' and 'admin' (even though they're the
same thing on my machines). I used an even simpler MWE
\documentclass{article}
\usepackage[no-math]{fontspec}
\begin{document}
Lorem $a$
\end{document}
Still gives the same error -- can't rebuild (or access, or anything) the
fontname db. If I comment out the call to fontspec, compiles fine. As soon as
fontspec gets involved...crash and burn.
So, we're back to fontspec, and/or luaotfload.
At this point, maybe I could ask someone else out there using MikTeX on
Windows machine, with all the latest updates installed, to see if they
can replicate the problem. If not, then its something weird on my
machines (although I haven't the foggiest what that might be). I've now
down installs/re-installs about 7-8 times in the past few days, and even
by random chance alone, you'd think I'd hit the right combination.
Unless of course, the problem lies with fontspec and luaotfload. ;-)
