SoftQuad Panorama uses a file called 'sdata.map' to map system-dependent SDATA characters. For standard ISO entity sets (ISOlat1, ISOgrk1, etc.), you generally do not need to modify the sdata.map file unless you want to change the font that is used to display the characters.
The HTI typically uses the public domain SPIonic font (Macintosh TrueType and Windows TrueType) for Greek characters. This font allows us to build all of the characters in the TEIgrk entity set. If you would like to use the TEIgrk entity set, you need to add the 'FontSpec' line to the 'Notation BMP System' section at the top of the sdata.map file and add the TEIgrk section to your sdata.map. When tagging a text with TEIgrk characters, the appropriate character entity references need to be used in the text, such as &ohragr;.
The next step is to add the TEIgrk entity declaration to the doctype declaration. This takes a form similar to the following:
<!ENTITY % TEIgrk PUBLIC "-//TEI TR1 W4:1992//ENTITIES Extra Classical Greek Letters//EN" "http://www.hti.umich.edu/sgml/panorama/TEIgrk.ent"> %TEIgrk
If you would like to use the SPIonic font for displaying the ISOgrk1 characters, you need to replace the ISOgrk1 section in the sdata.map with the version provided here.