the Latinisation of surnames in oblique cases is a moot point; many of the finer Oxford editors would disagree with your policy of keeping the surname uninflected and demanding to express the forename in full. 'hox' is a rather recherché form, about which my knowledge is nil. your love of Laconic prose suggested, probably wrongly, that you think liber neuter. recent cutting-edge research has suggested that the Romans lacked the letter 'w', so Guilelmus (so the English) or Gulielmus (so those on the continent) is the oft preferred form for William. there seems little point writing your 'dedication' in Latin if you are going to use an anachronistic method of dating: use the form a. d. N Id. Nou. a. D. MMV, where N represents a given integer, presuming you write this before the Ides. your decorous Latin 'example' did not match the order you posited; nonetheless, the donor's name should best appear just before the end, and of course you want to end with d.d., or perhaps d.d.d., should you feel like it. your 'optional (additional?) waffle' would cohere ill with the preceding dedication: if you are to write some Lat/Gk verse/prose, that should be placed immediately after the name of the recipient in the dative. in fact, it was only this morning that a couple of friends and i donated a book to a lady, in which we each wrote an elegiac quatrain, and then our initials followed by d.d. and date. i hope, quite naturally, that the book is worthy of your elegant effusions.