Strange behavior with cylindrical output

I output with MAKE PANO (1.18.5) some cylindrical panos, and some of them have the html5 setting (in the html page) to "never" others to "prefer".
Can't understand why...
For example a 5556 × 737px pano is ok for html5, a 5505 × 600px one not.
And there is no way to set the html5 to "prefer": it just don't work.

This is the report of Make VTour:

processing - 5505×600
- input: 5505×600.tif (cylinder, size=5505x600, fov=360x38)
- output: scene, preview, thumb, tiles
- multires: tilesize=512 levels=1 - 5506x600
- making images...
done.

processing - 5556×737
- converting cylinder to cube format...
done.
- input: *5556×737*.kro (converted cube, size=1770x1770)
- output: scene, preview, thumb, tiles
- multires: tilesize=512 levels=2 - 1770x1770 886x886
- making images...
done.

Thanks
Toni

Ok, I solved the problem:
on a previous thread, Klaus said:
"it depends on the 'converttocubelimit' config setting if a partial-sphere will be automatically converted to cube:
https://krpano.com/tools/kmakemul…verttocubelimit
The default setting is 360x45 in the most config files."

I just opened the multires.config file and changed the default setting (converttocubelimit=360x45) to 360x30.
That works.
Have to remember that HTML5 is only compatible with CUBE panorama.