Hello organplayer,
This previous topic covers it:
viewtopic.php?f=4&t=14902mdyde wrote:The only supported way currently (Hauptwerk v4.2.1) to change a 'favourite' assignment is to load the relevant organ and re-assign it to the favourite slot that you now want it to occupy. However, we do have an enhancement request logged for the future for Hauptwerk to have more comprehensive editing facilities for favourite assignments.
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Apart from assigning another organ to the relevant 'favourite' slot, if you really wanted to, you could actually cause the slot to be cleared by un-installing the relevant organ ('File | Un-install ...') and then trying to load the the organ via the 'favourite' slot. Hauptwerk will then see that the relevant organ is no longer present and clear the slot (set it back to blank).
(As mentioned there), the only way within Hauptwerk to clear an entry from a 'favourite organ' slot is to un-install the organ. However, it doesn't hurt to have the same organ assigned to multiple slots, so there's no real need to clear a slot anyway; you can just leave the organ harmlessly assigned there and it makes no functional difference if you aren't going to be using that particular slot anyway.
organplayer wrote:If there is no official function there should be an entry in a xml-file or whatever which can be edited manually?
Definitely please don't try to do that. Hauptwerk settings file are internal and undocumented, and you risk breaking your Hauptwerk installation. Editing Hauptwerk's internal files manually is very definitely not supported!
Best regards, Martin.
Hauptwerk software designer/developer, Milan Digital Audio.