... Child, HTMLtextObject, MUIA_HTMLtext_Contents, "This is a <b>Test</b>.", End, ...But don't forget, that HTMLtext.mcc uses some more memory and is slower than TextObject and it doesn't always make sense to use it.
For a completer example refer to the source of /text/hyper/moreHTML.lha to be found on Aminet including its sourcecodes.
C++
If you want to use HTMLtext.mcc using C++ please have a look at "dev/mui/MUIPlusPlus.lha" written by Nicholas Allen.