I just installed 5.3 x64 on a linux machine, using the *sudo dpkg -i .deb command. The installation seemed to go fine, and LO 5.3 is listed in the Start Menu. But 5.2 wasn’t removed, which surprised me. And opening either the old 5.2 shortcuts or the new 5.3 menu entries opens 5.2, not 5.3. There seems to be no way to open 5.3.
I thought 5.3 would overwrite 5.2. That didn’t happen, and it doesn’t seem to have installed beside it either. Rebooting did nothing.