How to reproduce:
Kdenlive 0.7.9 rev. 5427
Start a new project
Add Title Clip in Project Tree
Note that Duration is 5 seconds
Add some text
Note that Duration for the clip in Project tree is 5 seconds
Right click the clip / Clip Properties
Backspace out 05;00 and type 44;00
Note that Duration for the clip in Project tree is still 5 seconds
Go to the Clip Properties again
Note that Duration is 44;00 seconds
Drag the Title Clip to Video 1 and it is only 5 seconds long instead of 44.
If you create the clip with 44;00 it works as expected. But you still can't alter it.