The full version of article 45 and the annex doesn't change anything that I have said and in fact it rather affirms my understanding.
What the Basic Law says and what you are trying to sell is not the same.
The annex talks about following the Law which specifically in this case refers to article 45. Article 45 (in bold my emphasis) states "The ultimate aim is the selection of the Chief Executive by universal suffrage upon nomination by a broadly representative nominating committee in accordance with democratic procedures.
The main legal contention if you will is whether the nomination committee is subservient to the process i.e. whether the nomination committee is the means to an end or a means to an end.
Let goes through Article 45 one paragraph by one paragraph:
The Chief Executive of the Hong Kong Special Administrative Region shall be selected by election or through consultations held locally and be appointed by the Central People's Government.
Note the bold part. Along with election and local consultation, the paragraph essentially says Beijing has a say in the selection of Chief Executive. The use of "and" indicates it is not merely an alternative. This paragraph is also part of Article 45, which you can't just cut out because it is inconvenient for you.
Now to your favorite paragraph:
The method for selecting the Chief Executive shall be specified in the light of the actual situation in the Hong Kong Special Administrative Region and in accordance with the principle of gradual and orderly progress. The ultimate aim is the selection of the Chief Executive by universal suffrage upon nomination by a broadly representative nominating committee in accordance with democratic procedures.
The ultimate aim is universal suffrage with preconditions, not standalone universal suffrage. The statement doesn't just end after universal suffrage as there is no period there.
The specific method for selecting the Chief Executive is prescribed in Annex I: "Method for the Selection of the Chief Executive of the Hong Kong Special Administrative Region".
And in Annex I, the very first article repeats what is said in the first paragraph of Article 45. So there can be no ambiguity whatsoever of Beijing's authority in Chief Executive's selection process.
There is no legal contention, because the Basic Law actually spells things out very clearly. The issue here is the cherry picking on the part of pro-democracy politicians, selecting some words then disregarding the rest of the paragraph, kind of like what you are doing here.