Since (more or less) abandoning Windows in favour of Ubuntu, I've been using KDElive video editor. For the most part it's been a great thing, but just before Christmas I got a new (albeit secondhand PC). After installing Ubuntu on it, I didn't have much use for video editing until the recent spate of projects...
So I went to the Ubuntu Software thing and got myself a fresh install.
Now, sometimes the "old" PC would get a bit crashy when editing video, but the new install was horrific. Utterly useless...
I search around for a few days, tried a couple of other video editors, which, whilst stable, didn't offer the great functionality of KDEnlive... I decided to persevere.
Well, it turns out the Ubuntu Software centre thing has a *very* outdated and buggy version.
So, the fix is to give Ubuntu the correct and current repository to get the software from....
Open a terminal (CTRL-ALT-T)
and type the following....
sudo add-apt-repository ppa:kdenlive/kdenlive-stable
sudo apt-get update
sudo apt-get install kdenlive
Bingo. I don't think it's crashed once!
I hope this saves someone some time.