Halacha on rape -- hypothetical questions

The Rambam states explicitly that a rape victim or her father have the prerogative to refuse the marriage, but, in contrast to the Halacha regarding a seducer, if the girl and her father desire that the marriage take place, then the rapist must take the girl as his wife. Rambam goes on to specify that in this case, the girl is not granted a Ketuvah, because the man cannot divorce her. Here are my questions: (1) Suppose that the rape victim and her father did desire the marriage. How would this marriage be ritually enacted? Is there any ceremony or documentation associated with it (since there is apparently no Ketuvah)? (2) If the rape victim and her father desire the marriage and the marriage is enacted, it is clear that the husband can never initiate divorce proceedings. But what if the wife, at some time in the future, desires a divorce? How would she go about dissolving the marriage? Do her reasons for desiring a divorce matter? What if her husband does not want to divorce? What consequence is there of the fact that there is no Ketuvah? (3) Suppose the rape victim is a Ketanah, and the girl and her father desire the marriage (since otherwise she might have poor prospects in the future). How is this marriage effected? Doesn’t the girl continue to live under her father’s roof until she is a na’arah or a bogeret? If you could provide citations for the Halacha in each case, that would be greatly appreciated.

1. A common misconception is that the ketubah is part and parcel of the marriage ceremony. It is not. Reading the ketubah at the wedding is a custom, presumably introduced to create an artificial interruption between the first part of the wedding - kiddushin, the giving of the ring and pronouncing the bride "mekudeshet" - and the second part - nessuin - the chuoppah and 7 brachot. If the rape victim desired the marriage, it would be enacted like any other, with kiddushin and chuppah, without the ketubah. The ketubah itself was enacted according to the Talmud, to serve as a negative incentive for divorce. The ketubah (among other things) guarantees the wife payment in the case of divorce, and this, we hope, will make the husband think twice or thrice before divorcing his wife. Since the rape victim cannot be divorced against her will, this aspect of the ketubah is unnecessary. There are other ketubah obligations, for instance the obligation of a husband to provide food and lodging, which are not cancelled by the rape. 2. The woman would initiate divorce proceedings like in any other marriage, by suing for divorce in Beit Din. If the husband refuses and the Beit Din is convinced that the woman's claims are sincere/correct, they will enforce a divorce (i.e. they will force the husband to divorce her). 3. According to Torah law, a ketanah may be married by her father. The Rabbis forbade this practice. Presumably here, too the rapist would have to wait until the girl comes of age and agrees to the match.