If you are referring to TF50(2017) 2/2 Commission to UK, it was dated 12th of June, not May and it was their supposed negotiating position.
Well done, not only do you highlight your complete lack of understanding of the negotiations themselves, but of why may is making such a balls up of it.
The negotiating position outlines the pro rate payments for the projects and financial commitments we have made that go beyond the end of our membership. That includes several loans, and things like MEP and British EU worker pensions and severance pay (Farage gets €80K a year non-contributory pension for instance, plus €150K severance pay).
That is all they want to agree, how the final figure will be calculated. May;s response was to say they didn't agree. That was in June. The question then becomes, what part of the calculation do you not agree with. That is the answer we have been waiting for for talks to progress (that and a solution for Northern Ireland, another part of the agreed negotiation timetable).
As you know, May;s response to the question 'what don;t you agree with about the calculations and how would you amend it' was given at a speech in florence. She replies 'I'll send you £20 billion'.
So now they ask what is that £20 billion for? They still don;t know what she disagrees with in the calculations, she hasn't told them what calculations she wants, just a number.
Its like sitting in a restaurant, and when asked what you would like off the menu, replying 968 calories.
The reality is that the delays are down to us, and us alone, because may cannot give an actual answer, because the calculations of our liabilities will be at least €40 billion, €20 for ongoing access to the single market during transition, €20 for our pension and employment liabilities, plus whatever loans and other schemes we have signed up to. And boris and the other headbangers will have her head if she promises to meet those commitments at that much money, despite us already promising to pay for them.