Since the recent upgrade I made yesterday
I have had problems with libreoffice 5.1 calc

It dies suddenly with the following error:

X Error: BadMatch (invalid parameter attributes) 8
Major opcode: 42 (X_SetInputFocus)
Resource id: 0x700872d

I have upgraded Java and reinstalled LibreOffice to no avail.

Libreoffice worked ok before the upgrade.

Where are you installing libreoffice from?

I have fixed the problem by Zapping my old continuously upgraded Slackware-64-current and
starting over with a fresh new install of Slackware-64-current-(14.2_beta_2)

Actually that was a very good idea indeed as I also fixed another problem I had been putting off,
and the machine runs better than before, again.

I had been using a 5.1 of LibreOffice and it started acting up immediately after the upgrade.

But it wasnt too bad, since /home is on its own partition and things are backed up pretty well
so I just zapped "/" and "/usr" partitions and backed up some stuff from "/tmp"

So I have to reinstall some stuff like seaview and blast and inkscape (a regular fix anyway).

Unfortunately i also have to reinstall SPSS which is no fun actually.