These Sonus Paradisi sample sets need reinstallation for HW5:
Aeolian-Skinner (Oakland) surround
Altenbruch surround (dry does not need reinstallation)
Freiberg, dry and surround
Goerlitz, medium and full versions
Portland, Reuter surround
Rotterdam Transept Orgel, dry and surround
St. Omer, surround
St. Pons surround
Zwolle sample set, dry and surround
To reinstall a sample set, log into your Sonus Paradisi account, locate the "My Products" section, find the sample set entry, click the download links and download all the parts of the installation packages which you find there. Download all the parts into a single folder on your computer. All the parts should sit together in a single directory.
Run Hauptwerk and install the downloaded files into Hauptwerk in the usual way via the File menu, "Install organ, temperament or impulse response reverb..." option.
Good news, the most popular sample sets of Rotterdam Main, Caen and Utrecht (an many others) do not require reinstallation.