When submitting layout galleys, which is the default radio button selected (not the final version for publishing), whenever a new galley is submitted the previous one gets overridden.
Is this the standard workings of OJS?
If so, I would recommend allowing storage of different layout galleys. According to OJS in An Hour, the layout galley is supposed to be a template for the Layout Editor, right? So, if you have PDF and HTML galleys, you should be able to send 2 different templates.
Besides, the layout editor does not have access to the final edited text, unless it is sent via the layout galley.
The page should be very similar to the article pages for the editor/author/reviewer...
A header section with information about the article, the private area for work (layout galleys and proofreading).
If this is not correct, then I have a problem in my installation....