nam: [code omitted because of length] : version conflict for package "Tcl": have 8.5.10, need exactly 8.4 while executing "package require -exact Tcl 8.4"

I suggest you report a bug

You could try to satisfy the dependency by making a link from the 8.4 to the 8,5 -- might work if there is nothing deprecated in use:
sudo ln -s /usr/lib/libtcl8.5.so.0 /usr/lib/libtcl8.4.so.0

it gives a message after linking

ln:creating symbolic link ' /usr/lib/libtcl8.4.so.0' :file exists

OK, you have the library, so your executable is not looking in the right place for it. To list the libraries an executable needs, run the command:
ldd executable
Look at the tcl8.4 in the list -- should not have an explicit location, just a name, so it would get picked up from a normal library search. If it has an explicit location, and the location does not have the library, put the link there to the tcl8,4.
  If you installed the executable from an Ubuntu package, then report as a bug. If you downloaded from a ramdom location on the internet, then this is the sort of problem you'd expect. You can rebuild it yourself, or add the links to your system to make these sort of things work.