To get its job done efficiently KDE Partition Manager makes use of external tools to support a long list of file systems. You will probably have the required tools for the file systems on your computer installed already.
Always back up your data!
KDE Partition Manager has been designed and written with high diligence and an emphasis on data integrity. There is however always some danger involved when modifying a device's partition table or its partitions: There might still be a bug in KDE Partition Manager, an unexpected power failure or a problem with the computer's hardware.
For those reasons you should always have a back up of your important data before making any modifications with a tool like KDE Partition Manager.
The program's authors take no responsibility whatsoever if you lose any data while using KDE Partition Manager.