hi Adam,
use a formula on your report instead of the memo field. in that formula reference the memo field as a string var. then do a replace on the font table.
e.g.
stringvar m:= {your memo field}
replace(m, '\fonttbl{\f0\fnil\fcharset0 Calibri;}', '\fonttbl{\f0\fnil\fcharset0 Verdana;}');
m;
your syntax would vary as it'll be easier just to replace the font name instead of the whole table. e.g. replace the f# value with the one you want to use.
-jamie