Thanks for continuing to add to this most useful resource. One suggestion: I think you could be even more specific concerning which parts of the Foreword were written later. For instance, on page 16 (Vintage) Kinbote talks about the canceled readings that appear throughout the commentary. Since some of these were his own creation, he suggests that readers consider the variants "more valuable" than the final text. It seems likely to me that Kinbote penned his variants as he was writing the Commentary, since that process itself must have generated, in the moment, a particular desire to fill in a perceived absence. If so, then this part of the Foreword must have been added later.
On page 17, Kinbote writes, "As mentioned, I think, in my last note to the poem, the depth charge of Shade's death blasted such secrets and caused so many dead fish to float up, that I was forced to leave New Wye soon after my last interview with the jailed killer." This seems likely to have been added later as well, although the "I think" could be read as suggesting that Kinbote is anticipating including that info in the final note. Indeed, now that I think about it, I'm not sure that the final note ever does explain which secrets were revealed, or why Kinbote was "forced" to leave New Wye. If everyone knew already that he was Botkin, not Kinbote, what particular secret is Kinbote talking about? Is it possible that the "dead fish" floating up is an oblique reference to Hazel, the drowned daughter? Anyway, that's far afield. But are there other specific passages in the Foreword that were clearly written later?
Also, since Kinbote refers to the amusement park at both the beginning and end of his Foreword, is it fair to say that he must have written the Foreword on his very first night in Cedarn? Otherwise, he would know already that there was no amusement park "right in front of my present lodgings."