Not working Bibtex bibliography with XeLatex and TexStudio

Question

I'm working at my postgrade thesis, but I cannot make the bibliography work at all. I got my code structure from other thesis where everything worked, yet mine doesn't.

% !TeX program = xelatex
\documentclass[12pt]{article}
\usepackage[spanish]{babel}
\usepackage{fontspec}
\setmainfont{Calibri}
\usepackage[top=2.5cm, bottom=2.5cm, left=3.5cm, right=2.5cm]{geometry}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{indentfirst}
\usepackage{lipsum}
\usepackage{fancyhdr}
\pagestyle{fancy}
\fancyhf{}
\fancyfoot[C]{\fontsize{10}{12}\selectfont\thepage}
\usepackage{pdfpages}
\usepackage[babel,spanish=spanish]{csquotes}
\usepackage[backend=biber,style=apa]{biblatex}
\addbibresource{LibrosTexto.bib}
\begin{document}
\includepdf{FrontPage.pdf}
\setstretch{1.2}
\setlength{\parskip}{6pt}
\setlength{\parindent}{1.27cm}
\tableofcontents
\newpage
Escribiendo ñoñerías con muchas eñes y algún que otro acento para comprobar que no da problemas con el castellano de España. Escribiendo ñoñerías con muchas eñes y algún que otro acento para comprobar que no da problemas con el castellano de España. Escribiendo ñoñerías con muchas eñes y algún que otro acento para comprobar que no da problemas con el castellano de España. \cite{Prueba1} Escribiendo ñoñerías con muchas eñes y algún que otro acento para comprobar que no da problemas con el castellano de España. Escribiendo ñoñerías con muchas eñes y algún que otro acento para comprobar que no da problemas con el castellano de España. Escribiendo ñoñerías con muchas eñes y algún que otro acento para comprobar que no da problemas con el castellano de España.
\section{Análisis comparativo de libros de texto.}
\lipsum{1-10}
\cite{Random2}
\printbibliography[title={Referencias bibliográficas},heading=bibintoc]

There are some questions I should mention. First, Calibri font (hence I specifically use XeLatex) and text format specifications included are mandatory.

Second, since this is for a thesis where I use references from areas I hardly use again after this work and since I want to have refferences nicely tidy, I'm making more than one .bib file. As far as I know, this should not be a problem. Not sure than one file can be loaded without BibUnits, but I rather one mixed file than a harder problem.

Third, .bib file is in the very same directory where .tex is. I thought of making a folder inside .tex directory for bibliography. But since I cannot even run one bib properly, I give up with that idea.

Finally, when I compile (two F8 running on bib file and later two F5 running on tex file) I get the next message:

This is BibTeX, Version 0.99d (MiKTeX 23.5) The top-level auxiliary file: TFM - Borrador.aux I found no \citation commands---while reading file TFM - Borrador.aux I found no \bibdata command---while reading file TFM - Borrador.aux I found no \bibstyle command---while reading file TFM - Borrador.aux (There were 3 error messages)

Which I guess that points the problem into file reading. This makes sense since, even if I use \nocite{*}, nothing got printed at the end of text. However, I have no clue about what's going on or how to fix it. Am I compiling right? Where can the problem be?

I really appreciate help. Thanks.

PS: I can post an example of .bib file, but hardly think that'd be the problem.

===== UPDATE =====

Seems that compiling bibliography with biber is the key. But is it really? And it seems that magic comment % !BIB program = biber would do the job, but should I add it in the .tex file or in the .bib file?

Building upon all info I provided and now it seems that my original problem is solved, let's see if you enlighten me on this related doubt: Am I going to get more problems or incompatibilities due to XeLatex, languages and babel or something similar? Since it's going to be a long document, should I work with multiple .tex files and include them together or is it better to give up and continue with one file?