Version:           2.1.3 (using KDE 4.1.3)
OS:                Linux
Installed from:    Ubuntu Packages

When I restart or shutdown from KDE leave menu, a dialog pops up and states that the restart/shutdown was canceled by kget.  I found this annoying, so I went into kget's configuration to try to turn off this behavior.  I changed 2 settings that I recall:  1) turn on the mode to terminate kget when download is finished and 2) turn on the mode for KDE-wide progress indication with the not-per-file-but-rather-total-progress submode.  Immediately upon applying, kget crashed with the following traceback.  Now every time that I restart kget, kget crashes, presumably due to the settings in ~/.kde/share/config/kgetrc, as shown far below.  A work-around ~/.kde/share/config/kgetrc is also shown at the very end below.  (And why are there so many gray versus black adjustments while editing this field?)

Application: KGet (kget), signal SIGSEGV
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread 0xb5f846c0 (LWP 6597)]
[KCrash handler]
#6  0x0000000d in ?? ()
#7  0xb787206d in KJobTrackerInterface::unregisterJob (this=0xa0c1790, 
    job=0x9e82aa0)
    at /build/buildd/kde4libs-4.1.3/kdecore/jobs/kjobtrackerinterface.cpp:82
#8  0xb7e44624 in KAbstractWidgetJobTracker::unregisterJob (this=0xa0c1790, 
    job=0x9e82aa0)
    at /build/buildd/kde4libs-4.1.3/kdeui/jobs/kabstractwidgetjobtracker.cpp:50
#9  0xb7e473cc in KWidgetJobTracker::unregisterJob (this=0xa0c1790, 
    job=0x9e82aa0)
    at /build/buildd/kde4libs-4.1.3/kdeui/jobs/kwidgetjobtracker.cpp:93
#10 0xb7c6b3e8 in ?? () from /usr/lib/libkgetcore.so.4
#11 0xb7c50152 in KGet::reloadKJobs () from /usr/lib/libkgetcore.so.4
#12 0x08092542 in _start ()
#0  0xb8034430 in __kernel_vsyscall ()

~/.kde/share/config/kgetrc that causes this crash:
[Advanced]
EnableKUIServerIntegration=true
ExportGlobalJob=true
ExportSingleTransfer=false
KonquerorIntegration=true
QuitAfterCompletedTransfer=true

[Appearance]
ShowDropTarget=false

[Geometry]
ColumnWidths=531,109,100,100,100

[Internal]
FirstRun=false
LastDirectory[$e]=$HOME/Downloads/Intel
MainPosition=0,373

[KFileDialog Settings]
Height 800=400
Recent Files[$e]=$HOME/Downloads/Intel/idb_linux_docs.zip,$HOME/Documents/ISA/ARM/ARMv7/DDI0405C_arm_architecture_v7m_application_level_reference_manual.pdf,$HOME/Documents/ISA/ARM/ARMv5/14128.pdf,$HOME/Documents/ISA/ARM/8498.pdf
Width 1280=640

[MainWindow]
Height 800=380
MenuBar=Disabled
State=AAAA/wAAAAD9AAAAAAAAAegAAAF8AAAABAAAAAQAAAAIAAAACPwAAAABAAAAAgAAAAEAAAAYAGsAZwBlAHQAXwB0AG8AbwBsAGIAYQByAAAAAAAAAALQAAAAAAAAAAA=
Width 1280=488

[MainWindow][Toolbar kget_toolbar]
Hidden=true
ToolButtonStyle=TextUnderIcon
kgetrc (END)

an example ~/.kde/share/config/kgetrc that works around this crash once it occurs (perhaps your adjusting trues versus falses in the KDE-progress integration lines can pinpoint further):
[Advanced]
EnableKUIServerIntegration=false
ExportGlobalJob=false
ExportSingleTransfer=false
KonquerorIntegration=false
QuitAfterCompletedTransfer=true

[Appearance]
ShowDropTarget=false

[Geometry]
ColumnWidths=531,109,100,100,100

[Internal]
FirstRun=false
LastDirectory[$e]=$HOME/Downloads/Intel
MainPosition=0,373

[KFileDialog Settings]
Height 800=400
Recent Files[$e]=$HOME/Downloads/Intel/idb_linux_docs.zip,$HOME/Documents/ISA/ARM/ARMv7/DDI0405C_arm_architecture_v7m_application_level_reference_manual.pdf,$HOME/Documents/ISA/ARM/ARMv5/14128.pdf,$HOME/Documents/ISA/ARM/8498.pdf
Width 1280=640

[MainWindow]
Height 800=380
MenuBar=Disabled
State=AAAA/wAAAAD9AAAAAAAAAegAAAF8AAAABAAAAAQAAAAIAAAACPwAAAABAAAAAgAAAAEAAAAYAGsAZwBlAHQAXwB0AG8AbwBsAGIAYQByAAAAAAAAAALQAAAAAAAAAAA=
Width 1280=488

[MainWindow][Toolbar kget_toolbar]
Hidden=true
ToolButtonStyle=TextUnderIcon
kgetrc (END)