Data structure of article composing system supports version control and inline comment

Question

I need to define data structure for an article composing system with requirements:
1. It supports version control so that reader can look back older versions of article.
2. Inline comment is required so that reader can give feedback about a word, a sentence, …

I thought that FAT (File Allocation Table) structure meets above requirements. So I used it to implement data structure as below pictures.

Data structure version 1 of articles
(after there is version 2)
Data structure version 2 of articles

Could you please support to answer my questions:
1. In your opinion, is my implementation correct?
2. Is there any potential risk when I apply this data structure?
3. Do you have better suggestion for me?