I believe the only formats that can be imported into FTM are the ones you see in the drop down menu. (those the you mentioned).From the Text (Smart)document itself: File Open
Since most quasi word processing programs (publish, power point, etc)can export to a common word processing format is there any reason you can not export to a format that is supported by FTM and import that file.
FTM also imports HTML files, have you tried that?
If nothing else just do a copy all and paste that into the FTM text document.Copy all in current OS usually picks up the formatting code.