What's the best resource for finding good styles for instance for 1930s waltzes, like Diane, Alice Blue Gown, Dancing With Tears In My Eyes etc.?

Try typing the name of the song into the filter. If it’s not a well-enough known song, try a similar song that might be better known.

Matt, thanks for your reply. I did try that. The list that gets filtered seems to be heavily biased toward more recent titles. But I know there are individuals who, like me, have a special appreciation for jazz music of 90 years ago.
For instance, I would like to play with style variations on
https://www.youtube.com/watch?v=c34U45I_fsg
in BIAB. The incomparable Ruth Etting makes a smooth transition from ¾ to 4/4 at 1:40.

I think the closest styles that might be usable would be ones that include the Crooner Horns section. Try first clearing the style filter and then entering 'Crooner' in the Filter String.

Point to note is that the majority are 4/4, but the RealTrack may work in a 3/4 time signature. Worth experimenting.

Two RealTracks worth reviewing are:
- Horn Section, Background CroonerBigBand9-Part Sw 110
- Horn Section, Soloist CroonerBigBandShoutChorus11-Part Sw 110

Reginald,
I think you might get further if you don't use a prefabricated RealStyle, but combine suitable RealTracks yourself. In your Youtube example, I hear only a few strings and a rather simple piano accompaniment.
I put the RealTrack 1097:Piano Acoustic Rehearsal Waltz 085 into the piano track and RealTrack 2334: String Quartet, Rhythm Pop Chamber 085 into the strings track, and muted all other tracks (of course, this also depends on whether you have these RealTracks at all, they are not included in all program packages).
This already sounds quite good like your desired sound (of course, the sound quality of the real tracks is much better than that of the old recordings ;-).

Brille, this looks promising. I have the UltraPAK version for the Mac, so I think I have these RealTracks. I need to study the manual and tutorials to figure out how to do it. Thanks for your help.

Thanks AudioTrack. This looks like a good suggestion. Easy to try.

The charm of the original song is of course also due to the tempo modulations (playing ad libitum). This can be simulated with some effort in Band in a Box by specifying bar-related tempo changes with the F5 key.

Brille, I used your png image to create a song from scratch. It's definitely an improvement. Thanks for doing this. How did you generate it? Did you already have a template?
I understand the idea of bar-related tempo changes for simulating more realistic performance.
It seems to me that some of the more complicated chord variations emphasize one note of the chord with one style, but a different note with another style or a different beat in the measure. Makes it hard for a relative novice (like me) to predict what it's going to sound like.

Hello Reginald,

For licensing reasons (for title and melody) Band in a Box does not contain original songs. However, you can find suitable mgu and sgu files for many well-known songs in various sources on the Internet.
Some threads in the English forum deal with this, e.g." https://www.pgmusic.com/forums/ubbthreads.php?ubb=showflat&Number=618850".

You are right: Band in a Box automatically and randomly generates accompaniments based on the specified chord changes. So on the one hand they can sound new with each new click on "Generate and Play" (if you want to keep an accompaniment permanently, you can freeze the corresponding track by clicking on the "*" button) and on the other hand each style also interprets for example chord extensions like 6#9 differently.

Some of the demo songs for BIAB are actually the chord changes to popular songs. To my knowledge, there isn't an index of this, but when you audition a demo and find yourself saying 'this is familiar', that's why. So, you might get lucky.