To get them back you need to convert all hashnumbers (#
0AAD15FB90B7.dat) into regkeys and make a registry file of the complete list
(HKEY_CURRENT_USER\Software\Patchou\MsgPlus2\Nobody\CustSounds\<hash>). Next step is import that registry file into the registry, then in soundlibrary (Plus icon in main MSNM screen > open soundlibrary) select every single sound and click "edit sound"..by doing this Plus! will read the other information.
Edit: you're welcome
Tip for next time: make a soundpack out of all sounds you have (soundlibrary > add > export). Adding them back will be done in a jiffy then
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