Best I can tell I didn't dump the intro since it uses fixed length text with diacritics on the preceding line, and I guess we either overlooked it once Eien's translation was done, or I misplaced it somewhere.
At any rate, I have a PHP script I use to dump text like that now, so I've dumped and translated the intro.
I'm posting it here publicly to give Eien ni Hen a chance to provide feedback on the translation, or re-translate if preferred. If there is no feedback in a reasonable time, I'd say this should be fine.
The Earth has been attacked by a galactic empire.
Tetsuya and the empire's princess Kahm decide to marry for the sake of their planets' peace.
Afterward, Kahm marches on the empire to get her father, the emperor's permission.
However, Tetsuya is imprisoned and Kahm has been taken away.
You, as Tetsuya, have just taken to your feet to aid Kahm in acquiring the emperor's blessing.