Zdenek, following up with our offline conversation, I made small change to my installer manifest, so PerformUpgrade() method contains something like this:
s ^dk="Upgrade to version "_..#VERSION_" performed OK"
// a nyni muzeme volat kod v manifestu, a nebo taky ne a vse muzeme provest rovnou v teto metode
my simple installer script (CentOS7) - that I sent you offline - needs no changes, but before I call it, I do this:
[root@localhost install-scripts]# export MYVAR="kutac"
[root@localhost install-scripts]# echo $MYVAR
[root@localhost install-scripts]# ./silent-setup.sh 1
about to run only upgrade
then, looking at %SYS namespace what comes into ^dk global:
[root@localhost ~]# csession ens1
Node: localhost.localdomain, Instance: ENS1
^dk="Upgrade to version 1.2 performed OK"
^dk("aux")="toto je test"
--- as you can see, it works just fine. perhaps your problems are due to security / permissions rather then anything else.
feel free to contact me directly.