I'm on Slackware 14.1 (current) and using zsh as my shell but I think this might be a general question.

Problematic program is Synfig Studio which comes as a generalized binary package containing its own bin, etc, share and lib directories.

I have installed it into ~/Apps/Synfig which contains Synfigs local file structure.

Running it from the shell/terminal with /home/me/Apps/Synfig/bin/synfigstudio works as expected.
It picks up the library path without updating environment variables and the program finds all its components, plugins, icons and the like.

Running it from a script, however, required me to set up the LD_LIBRARY_PATH variable to get it running in the first place but it can't find any of its icons, giving me error messages like:

Repeated for all the assets.
Thing is, these files really do not exist there, yet if the program is launched from the shell then it picks its own local structure out correctly, not looking into /opt/.

Why is that and how can I set that up for the script?

Solution:
a cd to the Synfig local root folder before running the binary did the trick.

In the case of my script:

I do not really know that synfig, but I think there should be an environment variable pointing to that installation, otherwise it won't be able to find itself.
I think it has an environment setup file to run before executing any app.

Hm you mean synfig sets that up for itself? Shouldn't that work from wherever then? Shell or script?
Anyway. I've also created an account on the Synfig forum and I'll ask there as well.

I'm still interested in a general solution, if there is indeed one that isn't specific to me running this particular program like this but the whole process in general (as in differences between launching programs from an interactive running shell/terminal vs script (with shebang)).

P.S.: I tried both sourcing and executing the script, both run the program but it still can't find the icons and co in either case.

script is basically: