Were they on an external before ?
If so just copy the folder to the new drive, when you plug it in check that the volume letter matches the old.
If not Follow these MTU instructions to change the drive letter
http://blog.mtu.com/video-hoster/207
Windows 10 to find control panel right click windows icon select search and type “control panel” then follow the rest of the instructions.
Alternatively if your starting from scratch and have not copied your original songs.mdb to your new computer you can leave the drive letter at its default, open the Build songs database and use the Add folder or Add folder/subfolders buttons then navigate to the folder containing the kma files make sure you open it to see all the KMA files then press select, that will build them straight into your database.
Don’t do this if you already copied your original songs.mdb or you may get a load of duplicate errors.
Did your previous version of Hoster have the Backup/Restore function?
It would have been found from the Help menu this would make your new computer a clone of your old one.