What is usually said upon the slaughtering of the Aqeeqah (the sheep slaughtered on the seventh day from the child`s birth)?

It is desirable to say: "Bismillah Alrahman Alraheem, was`salatu Wa s`salamu Ala Sa`idenah Mohammad, O Allah, this Aqeeqah is from You and to You on behalf of ….."

Is it permissible to make up missed prayers at the times in which praying is disliked?

All perfect praise be to Allah,The Lord of The Worlds                                                                                                                                                                        It is permissible to make up missed prayers at any time even that in which praying is disliked. Absolute supererogatory prayer is forbidden to be performed at the times in which praying is disliked, and this also applies to Ihram and Istikhara prayers. However, there is no harm in offering prayers in Mekah during those times. And Allah Knows Best.

Am I permitted to perform more than a prayer within single ablution?

All perfect praise be to Allah, The Lord of The Worlds, and may His Peace and Blessings be upon our Prophet Muhammad and upon all of his family and companions.

You are permitted to pray as many as you could within one ablution and to recite Quran so long as your ablution isn't nullified. And Allah Knows Best.

Should vowed fast be offered in consecutive days, or not?

Vowed fast should be offered in line with what was originally intended by the vow-maker, either consecutively, or not.