You may notice that the colon at the end of the "name or address" text looks a bit smaller than the rest of the text. This is because Japanese uses two-byte fixed width fonts and Latin-based languages use single-byte proportional. The hardcoded colon is smaller because it appears in a different font from all the Japanese characters.
Here's what it should look like, courtesy of my graphics editor:
I don't think I got the alignment of the colon quite right (I'm probably not even using the correct font), but it's close enough. See how the characters in the first two lines line up nicely one over the other? The colons need to be rendered in the Japanese font or the results will appear somewhat less than professional to native speakers.
I hate to make this recommendation, as it's probably going to mean a lot of revising of not only the original English phrases but all localized versions, but the colons (along with any other hardcoded punctuation) really need to be in the phrases.
In other words, they need to be handled in the same manner as the question marks, which were correctly included in the phrases. I say "correctly" not only because they can be rendered in the correct font, but also because they can be omitted if necessary. For example, the question mark isn't needed after the "forgot your password?" string because that phrase is better translated without the interrogative.
To be sure, I'd just as soon have the option of removing the trailing colons altogether, as Japanese forms generally (barring rare exceptions) omit them, as in the following random example:
I don't know if it's possible or desirable, but you may be able to avoid moving all the colons to the phrases by creating a "colon" phrase and using it to replace all the hardcoded colons. If you go this route, please be sure to allow for the possibility of a null value for that phrase, so colons can be omitted if necessary.
Thanks for your attention to this matter.