Problems with the Rightside page using reledpar/reledmac

0. How to make a MWE

I have taken the liberty of cleaning up your sample code.

TeX.SX requires users to post a Minimal working example (MWE). This means: Your sample code should contain only what is strictly necessary (minimal) to effectively produce a document (working) that still exhibits your issue (example).

The rationale is: removing all the unnecessary "noise" from your code helps the community help you.

Having removed all the superfluous packages from your code, I still can see the two problems you addressed.

1. Solving the awful spacing

Reading the manual, as always, pays off. Specifically, let's look at p. 71:

You should put a standard sectioning command (\chapter, \section etc.)

• either outside of a \pstart ... \pend environment
• or as the optional argument of a \pstart, in which case it will be executed right before said \pstart (so, effectively, both solutions are the same).

\pstart[\section{Title}] Text... 

Also please take the following advice to improve (your code and) your document:

• Leaving a line empty, in (La)TeX, generally makes a new paragraph. But with reledmac, the right way to make a new, fully functioning paragraph, is explicitly: write \pend and then \pstart. You should avoid leaving empty lines inside a \pstart environment, because it can make for odd spacing or lineation.
• When you need to add a new (sub)section, proceed as described above: \pend \pstart[\subsection{Title}].
• reledpar works only if you have the same number of explicit paragraphs on both sides. In the following example, I have balanced the paragraphs from your sample text.

\documentclass[12pt]{article} \usepackage[a6paper]{geometry} % only for the sake of presentation \usepackage{reledmac} \usepackage{reledpar} \begin{document} \begin{pages} \begin{Leftside} \beginnumbering \firstlinenum{2} \linenumincrement{2} \pstart[\section{LOREMMMMM}] Cras malesuada quam vel eros ornare condimentum. Nulla enim ante \pend % \pstart (more text) \pend \pstart (more text) \pend \pstart (more text) \pend \endnumbering \end{Leftside} \begin{Rightside} \beginnumbering \numberlinefalse \pstart [\section{LOREM IPSUM}] Fusce a porttitorauris sed augue tincidunt lacus iaculis quis.\footnoteA{Noooooote} \pend \pstart [\subsection{IPSUM}] Fusce a porttitor mi. Cras malesuada quam vel eros ornare condimentum. \pend \pstart [\subsection{LOREM}] Fusce a porttitor mi. Cras malesuada quam vel eros ornare condimentum. \pend \pstart [\subsection{Commento}] Fusce a porttitor mi. Cras urna. \pend \endnumbering \end{Rightside} \end{pages} \Pages \end{document} 

Now the spacing is up to LaTeX's reputation for elegant typesetting! Onwards to fixing the footnotes.

2. Solving the misplaced footnotes

Here we have an unfortunate case where the info in the manual (p. 20) appears to be wrong:

Line numbering can be disabled with \numberlinefalse. This feature must be used with caution. ... It could be used in the following cases:
You want only familiar footnotes, not critical footnotes ...

This is not (no longer?) the case. In fact, if you use \numberlinefalse in a numbered portion that contains even familiar footnotes, you run into the above issue, of footnotes shifting to a later page in the document.

So you should keep the numbering enabled, but make it "undetectable" to the eye. Luckily, we can take the advice on the next page:

You do not want to have the line number in the margins, but do want to use critical footnotes. In this case, set \firstlinenum to a big value, such as 100,000.

\documentclass[12pt]{article} \usepackage[a6paper]{geometry} % only for the sake of presentation \usepackage{reledmac} \usepackage{reledpar} \begin{document} \begin{pages} \begin{Leftside} \beginnumbering \firstlinenum{2} \linenumincrement{2} \pstart[\section{LOREMMMMM}] Cras malesuada quam vel eros ornare condimentum. Nulla enim ante \pend % \pstart (more text) \pend \pstart (more text) \pend \pstart (more text) \pend \endnumbering \end{Leftside} \begin{Rightside} \beginnumbering \firstlinenum{100} \pstart [\section{LOREM IPSUM}] Fusce a porttitorauris sed augue tincidunt lacus iaculis quis.\footnoteA{Noooooote} \pend \pstart [\subsection{IPSUM}] Fusce a porttitor mi. Cras malesuada quam vel eros ornare condimentum. \pend \pstart [\subsection{LOREM}] Fusce a porttitor mi. Cras malesuada quam vel eros ornare condimentum. \pend \pstart [\subsection{Commento}] Fusce a porttitor mi. Cras urna. \pend \endnumbering \end{Rightside} \end{pages} \Pages \end{document} 

And here is the desired outcome: