[Roy Dennis]

What I think you should do to remove all records from the system is from the "Build songs database" dialog Highlight all the folders showing that are in the list then press the "Exclude Folders" button. After doing this press the "Build Database "button that will build a zero count songs .mbd.
Next press the "Excluded folders " button at the top of the dialog and remove all the files that you removed earlier except the Recycle.Bin,C:\Program Files(x86) & C:\Windows. or any others that you know don't have music in. This will then allow those files to be indexed again but they may still have their .KMH headers with them that may be corrupted so delete these.kmh headers.
Now it will be like starting from scratch.

Regarding your book id # I did point this out earlier from the file you sent me, it does seem very high, in theory 25,500 songs imported as only 15 songs to an ID would only give you an id of 163399. So something strange is happening there.
It may be that it is counting on top of your existing ID # with the new imports that is why it needs all existing data removed from the system if you don't remove the existing .kmh files it will keep using those book id's as it is in the headers.
A lot of problems like this occur by deleting files Via Windows Explorer instead of using the Edit Dialog in Hoster but removing the folders from the build database option it should tell you xxx amount of files removed.