I found out that yet another piece of software unfortunately can't be used for Freesound uploads.
The sounds can be used royalty free by the purchaser of the downloads in any context except:
1. To make another sample/sound effect CD or database, even if the material has been manipulated.
2. To upload the individual sounds to a sound database to be used by others
3. Any sound file CD/database or multimedia sound library.
4. Any multimedia or game product DVD/CD or web game that includes isloated sounds from PowerFX.