Did you also try to install it via OPM in Laz4 already?
Indeed, why do you manually install a package when it is in
OPM? It does not require manual downloading, unpacking, opening, and rebuilding... Just install "
OnlinePackageManager" first, and after rebuilding, open it and install your package through it.
However, I see that the versions of this package in
OPM and
SourceForge are identical (almost). So the problem is in the installation method or in the OS. In Linux, there have been problems reported due to the rebuilt executable ending up in the user folder, since it cannot modify the system file (root).
Make sure you are running the right file. To do this, use "
./startlazarus", which automatically finds the right one.