Dear Arthur,
No, these are relevant messages.
It looks like, the precompiled package of Flair-Geoviewer is not compatible with Centos 8 since it only has glibc version 2.28.
However, you should be able to compile it from the .tgz package. To do so you will need some extra packages, like:
- python36-devel
- tk-devel
- libX11-devel
This should fix the first warning and error message.
About the second warning message. Do you still get an error message with the check_fluka.sh script after installing pillow?
If yes, it could mean, there there are multiple python3 installed. Can you check the output of these commands:
python3 --version
which python3
Cheers,
David