It appears I cannot open an RTF file saved from TMSFMXRichEditorRTFIO1 with TMSFMXRichEditor1.LoadFromFile(filename) but I can open the same file if I use
the default operations of the Toolbar Open icon and select the file from my machine.
An exported RTF file needs to be loaded in the TMSFMXRichEditor via TMSFMXRichEditorRTFIO1.Load method.