On Linux timeseal.Linux is expected to be in one of these directories
. (current directory)
~/.eboard
~/share/eboard
/share/eboard
/usr/local/share/eboard
/usr/share/eboard
/usr/share is for architecture-independent data according to the FHS standard. However timeseal.Linux is an architecture-dependent file. Ideally it should be possible to install it into e.g.
/usr/lib/eboard/timeseal.Linux or
/usr/local/lib/eboard
too. At the moment eboard does not seem to accept those locations.