Getting a bit off topic here: apologies to GimpChat.
I can reproduce that error. Looks to me that recent Mint update breaks both the Krita versions commonly available. Sometimes I think that Mint has lost-the-plot. Maybe that is why I use PClinuxOS
What you can do is install the latest from an ubuntu ppa Mentioned ppa earlier.
The procedure would be
Uninstall krita, krita-data using synaptic
Add the ppa to the sources list. This involves opening a terminal and using the command
sudo add-apt-repository ppa:dimula73/krita
Once that is done, back to synaptic,
refresh the package list, look for krita 2.9 and install it.
Works here, I know all this is difficult for a new linux user but you will get there.
A video demo of the above in a Mint 17.1 VM
https://youtu.be/B5xAseWIOP0 5 mins