Importing some HTML based email has shown that SPAN and DIV are not handled properly. SPAN should also allow for font changes, I was able to fix this by copying the file name/size handling chunk from the STYLE section below up to the span section under the existing "if pos('COLOR:',clr) = 2 then" block. There is no support at all for DIV, which I was able to get rendering properly by treating it exactly like the <BR> tag on the /DIV. This corrects my specific test case.
We can confirm we extended the HTML import with support for SPAN font settings and also added support for DIV. This will be included in the next release.