Just installed 0.7.5 from Arch hoping I would be able to work with Kdenlive without constant crashes (like I had with 0.7.4), no luck I'm afraid.
Running from CLI gives me this..

kdenlive(5965)/kdeui (KNotification) KNotification::slotReceivedId: 0
kdenlive(5965)/kdeui (KNotification) KNotification::close: 0
kdenlive(5965)/kdeui (KNotification) KNotification::~KNotification: -2
WARNING: deleting stale lockfile /home/kelp/.kde4/data/stalefiles/kdenlive/mika.kdenliveWQIfile_%2Fhome%2Fkelp%2Fkdenlive%2Fmika3dJNdWQI.lock
kdenlive(5965)/kdeui (KNotification) KNotification::slotReceivedId: 0
kdenlive(5965)/kdeui (KNotification) KNotification::close: 0
kdenlive(5965)/kdeui (KNotification) KNotification::~KNotification: -2
kdenlive(5965)/kdeui (KNotification) KNotification::slotReceivedId: 0
kdenlive(5965)/kdeui (KNotification) KNotification::close: 0
kdenlive(5965)/kdeui (KNotification) KNotification::~KNotification: -2
KCrash: crashing... crashRecursionCounter = 2
KCrash: Application Name = kdenlive path = pid = 5965
sock_file=/home/kelp/.kde4/socket-asla/kdeinit4__0


It happens random when I click somewhere on the timeline or menu.
Recovering the project often doesn't recover very well.. clips are 'randomly' cut from the timeline.

I'm working from KDE or openbox, makes no difference it seems.
All needed modules are installed (as config-wizard states) - MLT version 0.4.4-1

I don't know what info I should provide to help others help me, so please let me know.

You probably have remainings of old MLT installs. Can you check?