HI @steffens,
Thanks so much for your help, now it's working.
root cause: The interface between the chair and the screen 
!
Explanation: I went on and downloaded the latest version (5.4.0) and it worked immediately... curious to know why I diff the config files with the previous version, and ooops, filebeat.yml 5043 port config was pointing to elasticsearch (port 5043)!
I did put it as the guide (and as posted here) but since in 5.3.0 permissions were wrong for filebeat user
(issue Filebeat.yml must be owned by the beat user (uid=0) or root)
when I fixed it I had the file already opened in another sublimeText window, so It got overwritten silently later and I guess I missed somehow the sublime notification of this refresh...
Now in 5.4.0 permissions are ok out of the tar.gz , and I have the latest version, yay!
apologies for the time wasted, thanks a lot for your support!