Menu Launch Name

[Mick Sulley]

Running Mint 18 Cinnamon.

I have a version of DigiKam installed from repo that I have called 
'digikam5', that is fine.  I have also installed 2 versions via 
AppImage, both show on my menu as 'digiKam'.  I just went into the menu 
configuration, selected properties and renamed them as 'digiKamX' and 
'digiKamY' but when I look in the menu they are both still called 'digiKam'

How can I change the display name for digiKam?  This method works for 
all other applications.

Mick