Text: in june 2011, the european commission published a proposal for a new roaming regulation.

Correct capitalization: In June 2011, the European Commission published a proposal for a new roaming regulation.

Text: did someone email you a a8 file and you're not sure how to open it? maybe you have found a a8 file on your computer and wondering what it's for? windows might tell you that you can't open it, or in the worst case, you might encounter a a8 file related error message.

Correct capitalization: Did someone email you a A8 file and you're not sure how to open it? Maybe you have found a A8 file on your computer and wondering what it's for? Windows might tell you that you can't open it, or in the worst case, you might encounter a A8 file related error message.

Text: splendid gilded cupolas rose over the roof, and between the pillars that surrounded the whole building stood life-like statues of marble.

Correct capitalization: Splendid gilded cupolas rose over the roof, and between the pillars that surrounded the whole building stood life-like statues of marble.

Text: now that is really really cheap compared with some of the swiss dive watches. (and not to mention citizen has so much more functionality built into their watches)

Correct capitalization:
Now that is really really cheap compared with some of the Swiss Dive watches. (and not to mention Citizen has so much more functionality built into their watches)