Unable to use "+LaTeX_HEADER: \input{...}" with latex-preview-fragment

[Mark Edgington <edgimar@gmail.com>]

I attempted recently to have org-mode use a preamble file when
previewing latex-fragments.  I used a line like the following:

    +LaTeX_HEADER: \input{relative-path-to-file.tex}

Unfortunately, the file referenced by the \input{} command doesn't get
copied to the location where the preview tex file is compiled.
Certainly a way of making it work would be to use an absolute path
instead of a relative path, but I really want to have a self-contained
portable directory containing both org-mode and preamble files.

Would it be possible or sensible to make an option which makes
latex-preview-fragment parse +LaTeX_HEADER lines for \input{}
commands, and attempt to copy the input files to the preview
compilation-folder?

Regards,

Mark