Are any other source-language texts, such as the Textus Receptus available in PT7 or PT8? The Textus Receptus would be a useful reference when checking why a translation seems to differ from the UBS/Nestlé-Alland.
The Robinson Pierpoint Byzantine text (Greek Orthodox tradition) is available as an option to the UBS Greek. Either open the BYZ project or open the Source Language Tools, then click “Use Byzantine Text” to use that instead of UBS Greek.