Ok. I think it is some sort of file problem.

If I use your URL it works fine.
If I use some script to download your data to local file every 60 seconds:

 while true ; do curl -s aagsolo.lunatico.es:10800/cgi-bin/cgiLastData -o cgiLastData; sleep 60; done

and change the File option to point to the full path of the file cgiLastData then same problem as before. I get a straight line
connecting the startup value and the first update then no more updates.
Permissions fine - it is rw rw r ....
Head scratching...............
Will go for break and think about it.
Cheers.

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