@smokemachine @Moray
1st vacation is more important as hacking 😀 enjoy your free time.
The error messages:

@smokemachine @Moray
Thank you for your quick help. I did some test now and my results are:

@donaldh
Thank you very much for your help.
perl Configure.pl --backend=moar --gen-moar --moar-option='--has-libffi' was the solution.
libffi8 and libffi-dev was installed but not found by Configure.pl

@lizmat thank you for your answer.
Perl is installed and all other requirements are installed on the Armbian distro. The Hardware is a Bananapi bpi m2 Berry, a bit exotic but working. I can send you the full output of the perl Configure.pl if you can give me an E-Mail address.

@smokemachine I found the problem. If I use vim or gvim to edit the configuration file then this problem occur. With other editors it will work. I don't know why. Thank you for your help.

@smokemachine Your version of my script looks better as my elsif chain. But the problem with 'watch' still exist.

@smokemachine yes the error pop up if I change the config file. The changes I will test tomorrow, after a bottle wine is is not the right time 😉 to test...