biber, two issues

[mario chiari]

Hi

I am not getting it right with biber. Two issues:

1. if I try >>> /usr/local/texlive/2018/bin/x86_64-linux/biber --help
 
I get 

Unicode::Collate object version 1.25 does not match bootstrap parameter 1.21 at
/loader/HASH(0x2221ce0)/DynaLoader.pm line 210.
Compilation failed in require at /loader/HASH(0x22212c0)/base.pm line 100.
	...propagated at /loader/HASH(0x22212c0)/base.pm line 109.
BEGIN failed--compilation aborted at
/var/www/tmp/inc/lib/Unicode/Collate/Locale.pm line 6.
Compilation failed in require at /var/www/tmp/inc/lib/Biber/Internals.pm line
18.
BEGIN failed--compilation aborted at /var/www/tmp/inc/lib/Biber/Internals.pm
line 18.
Compilation failed in require at /loader/HASH(0x2221620)/parent.pm line 16.
BEGIN failed--compilation aborted at /var/www/tmp/inc/lib/Biber.pm line 5.
Compilation failed in require at script/biber line 17.
BEGIN failed--compilation aborted at script/biber line 17.

(I still have texlive 2016, and /usr/local/texlive/2016/bin/x86_64-linux/biber
--help works fine)
I suspect it is a Perl issue, but I do not know anything about perl. 

2. I use a php script, say my.php, to create a .tex file. It also calls latex,
(2016) biber, and pdflatex to produce final outputs.

If I run it from terminal - php cli, as root - it works fine. If I run it from a
web browser (http://localhost/my.php), biber does not seem to be called at all.
In the latter case, files are owned by user apache, and I suspect that biber
does not like that.  How do I fix it? 

Thanks
Cheers
mario