The DEMO button was added because some users want to hear how a RealTrack sounds in their song before adding the RealTrack to their song. For that feature to work the developers had to limit instrument selection to track/instrument. Otherwise you can end up with two RealTracks trying to occupy one track.

The +++ Band-in-a-Box Wishlist +++ forum section is the place to request changes. You need to request a change because this is not a bug; the limitation exists to support the DEMO button.

I know English is not your native language and you are worried your request maybe misunderstood. May I suggest that you use the wording in the quote below and also provide a link to this discussion.

Quote
Please change the MultiPicker RealTracks tab operation so a user can first select a RealTrack and then select a mixer track. This is in addition to the current method of first selecting a mixer track and then a RealTrack.

Jim Fogle - 2025 BiaB (Build 1128) RB (Build 5) - Ultra+ PAK
DAWs: Cakewalk Sonar - Standalone: Zoom MRS-8
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