building the book - does not work

HI,
I tried to build the book using the instructions provided in the readme.
There are number of issues:
in the instructions:
python -m venv env
source env/bin/activate
pip install requirements.txt
jupyter-book build book/

-r option is missing, instead of pip install requirements.txt should be pip install -r
requirements.txt

Next, command:
jupyter-book build book/

generates number of errors/warnings:
Running Sphinx v5.0.2
making output directory... done
[etoc] Changing master_doc to 'intro'
checking bibtex cache... out of date
parsing bibtex file /home/jozef/ismir23-tutorial/book/references.bib... parsed 13 entries
myst v0.18.1: MdParserConfig(commonmark_only=False, gfm_only=False, enable_extensions=['colon_fence', 'dollarmath', 'linkify', 'substitution', 'tasklist'], disable_syntax=[], all_links_external=False, url_schemes=['mailto', 'http', 'https'], ref_domains=None, highlight_code_blocks=True, number_code_blocks=[], title_to_header=False, heading_anchors=None, heading_slug_func=None, footnote_transition=True, words_per_minute=200, sub_delimiters=('{', '}'), linkify_fuzzy_links=True, dmath_allow_labels=True, dmath_allow_space=True, dmath_allow_digits=True, dmath_double_inline=False, update_mathjax=True, mathjax_classes='tex2jax_process|mathjax_process|math|output_area')
myst-nb v0.17.2: NbParserConfig(custom_formats={}, metadata_key='mystnb', cell_metadata_key='mystnb', kernel_rgx_aliases={}, execution_mode='force', execution_cache_path='', execution_excludepatterns=[], execution_timeout=30, execution_in_temp=False, execution_allow_errors=False, execution_raise_on_error=False, execution_show_tb=False, merge_streams=False, render_plugin='default', remove_code_source=False, remove_code_outputs=False, code_prompt_show='Show code cell {type}', code_prompt_hide='Hide code cell {type}', number_source_lines=False, output_stderr='show', render_text_lexer='myst-ansi', render_error_lexer='ipythontb', render_image_options={}, render_figure_options={}, render_markdown_format='commonmark', output_folder='build', append_css=True, metadata_to_fm=False)
Using jupyter-cache at: /home/jozef/ismir23-tutorial/book/_build/.jupyter_cache
building [mo]: targets for 0 po files that are out of date
building [html]: targets for 34 source files that are out of date
updating environment: [new config] 34 added, 0 changed, 0 removed
reading sources... [100%] intro
/home/jozef/ismir23-tutorial/book/ch1_intro/tutorial_structure.md:4: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/tutorial_structure.md:18: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/tutorial_structure.md:29: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/why_wavelets.md:21: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/why_wavelets.md:32: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/why_wavelets.md:45: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/why_wavelets.md:57: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/why_wavelets.md:78: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch1_intro/why_wavelets.md:90: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch6_dtfa/ddsp.md:5: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch6_dtfa/ddsp.md:26: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch6_dtfa/ddsp.md:37: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/ch6_dtfa/dtfa.md:23: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:6: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:26: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:32: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:61: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:66: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:90: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:105: ERROR: Document or section may not begin with a transition.
/home/jozef/ismir23-tutorial/book/intro.md:110: ERROR: Document or section may not begin with a transition.
looking for now-outdated files... none found
pickling environment... done
checking consistency... done
preparing documents... done
writing output... [100%] intro
/home/jozef/ismir23-tutorial/book/intro.md:62: WARNING: 'myst' reference target not found: kymat.io
/home/jozef/ismir23-tutorial/book/intro.md:12: WARNING: could not find bibtex key "patil"
/home/jozef/ismir23-tutorial/book/intro.md:14: WARNING: could not find bibtex key "dafx vahidi"
/home/jozef/ismir23-tutorial/book/intro.md:14: WARNING: could not find bibtex key "andreux"
/home/jozef/ismir23-tutorial/book/intro.md:20: WARNING: could not find bibtex key "Lostanlen"
/home/jozef/ismir23-tutorial/book/intro.md:27: WARNING: could not find bibtex key "jasmp"
generating indices... genindex done
writing additional pages... search done
copying images... [100%] assets/vl.jpeg
copying static files... done
copying extra files... done
dumping search index in English (code: en)... done
dumping object inventory... done
[etoc] missing index.html written as redirect to 'intro.html'
build succeeded, 27 warnings.

The HTML pages are in book/_build/html.

===============================================================================

Finished generating HTML for book.
Your book's HTML pages are here:
book/_build/html/
You can look at your book by opening this file in a browser:
book/_build/html/index.html
Or paste this line directly into your browser bar:
file:///home/jozef/ismir23-tutorial/book/_build/html/index.html

===============================================================================

Start with the README build instructions and run the documented virtual-environment, dependency-installation, and jupyter-book commands. Then inspect the reported files under book/, including intro.md, ch1_intro/tutorial_structure.md, ch1_intro/why_wavelets.md, ch6_dtfa/ddsp.md, and ch6_dtfa/dtfa.md. Done means the book builds without the reported errors and the listed reference warnings are resolved or explained.