ox-publish: no HTML output but no errors

[c . buhtz]

Hello,

I tried to use ox-publish to create HTML files out of my org files 
(created via org-roam v2) using the Tutorial 
https://orgmode.org/worg/org-tutorials/org-publish-html-tutorial.html .

The output directory is empty but I also do not have a valuable error 
output. On that point I did not know where to go.
I evaluatet the code (below) via C-x C-e and then did M-x 
org-publish-project RET org RET.

The message buffers looks like this

20 (("org-notes" :base-directory "~/tab-cloud/my.org-roam/" 
:base-extension "org" :publishing-directory "~/tab-cloud/_transfer/html" 
:recursive t :publishing-function org-html-publish-to-html :\
    headline-levels ...) ("org-static" :base-directory 
"~/tab-cloud/my.org-roam/" :base-extension 
"css\\|js\\|png\\|jpg\\|gif\\|pdf\\|mp3\\|ogg\\|swf" 
:publishing-directory "~/tab-cloud/_transfe\
    r/html" :recursive t :publishing-function org-publish-attachment) 
("org" :components ("org-notes" "org-static")))
 21 Loading /home/user/.org-timestamps/org-notes.cache...done
 22 Publishing file 
/home/user/tab-cloud/my.org-roam/20211109001227-programming_languages.org 
using ‘org-html-publish-to-html’
 23 48 files scanned, 45 files contains IDs, and 47 IDs found.
 24 45 files scanned, 45 files contains IDs, and 47 IDs found. [6 times]
 25 user-error: Unable to resolve link: 
"c6693020-d065-4d4f-8be8-650c66eee3e6"
 37 Publishing file 
/home/user/tab-cloud/my.org-roam/20211109001227-programming_languages.org 
using ‘org-html-publish-to-html’
 38 45 files scanned, 45 files contains IDs, and 47 IDs found. [7 times]
 39 user-error: Unable to resolve link: 
"c6693020-d065-4d4f-8be8-650c66eee3e6"

This is the piece of code (in scratch buffer) IMHO very near to the 
tutorials example

;https://orgmode.org/worg/org-tutorials/org-publish-html-tutorial.html
(require 'ox-publish)
(setq org-publish-project-alist
      '(
       ("org-notes"
       :base-directory "~/tab-cloud/my.org-roam/"
       :base-extension "org"
       :publishing-directory "~/tab-cloud/_transfer/html"
       :recursive t
       :publishing-function org-html-publish-to-html
       :headline-levels 4             ; Just the default for this 
project.
       :auto-preamble t
      )
      ("org-static"
       :base-directory "~/tab-cloud/my.org-roam/"
       :base-extension 
"css\\|js\\|png\\|jpg\\|gif\\|pdf\\|mp3\\|ogg\\|swf"
       :publishing-directory "~/tab-cloud/_transfer/html"
       :recursive t
       :publishing-function org-publish-attachment
      )
      ("org" :components ("org-notes" "org-static"))
      )
)

I have round about 50 org files in my archive. There is one error about 
a dead link. But this should be no problem. Dead links are OK for me and 
also a "valid content" in the context of a Zettelkasten. A dead link is 
not a reason to stop the whole process.

The "html" folder is absolute empty. Nothing in there.

How can I go on with diagnosis?