Question 1.

I upgraded my Ubuntu system to the latest KDE 4.12 and a lot of them are crashing. Karbon, Krita, Kate, Calligra flow almost everyone I open crashes when I try to open or save a file or fail to starts altogether .

Is there some way to test if all the libraries they require are present on my system and fully compatible?
At least there should some way to obtain crash diagnostics.

The system is an Ubuntu 12.04.4 LTS 32bit.

2. Question 2.

What repository does Ubuntu use for install kubuntu and KDE SC ?
Are kubuntu-desktop and Calligra installed from the same repositories?
Could some repository conflicts causing this issue?

The primary form of crash diagnosis we can perform is through the generation of a backtrace on your system. When the crash assistant launches, click the "Developer Information" tab - this will cause it to generate backtrace. Please post one example of that here.

From what I am aware, Ubuntu and Kubuntu share the same mainline repositories - so KDE itself, along with all associated applications such as Calligra should come from there. If everything came from the same repository, then it should be compatible.

bcooksley wrote:The primary form of crash diagnosis we can perform is through the generation of a backtrace on your system. When the crash assistant launches, click the "Developer Information" tab - this will cause it to generate backtrace. Please post one example of that here.
...

The crash assistant doesn't even appear. The programs vanish immediately.

Unfortunate - this means you're experiencing a particular kind of crash which the crash assistant can't intercept.
Are you familiar with launching applications under a debugger?

bcooksley wrote:Unfortunate - this means you're experiencing a particular kind of crash which the crash assistant can't intercept.
Are you familiar with launching applications under a debugger?

I can give that a try. I am familiar with installing and compiling software.

Type "gdb application_name", then type "run". When it crashes, type "thread apply all bt". Post the result here. Optimally, install the -dbg or -debug packages for the program you're launching beforehand.

Greetings!