Dick, here is a macro that centers a dot under the following letter; I have
used it successfully with Arabic transcriptions. Please show this to BB, thanks.

\def\underdot#1{\save6\hbox{#1}\hbox to 1wd6{\hfil\lower\desc\hbox{.}\hfil
	\hskip-1wd6\box6}}	% puts dot underneath the next character

Here \desc is defined to be the depth of descenders in the current point size;
one redefines \desc at the same time as defining \rm and \it etc.

An ex-Roumanian student here does a similar thing with commas, but if necessary
it would be easy to make up new characters with METAFONT.