Hi,
I'm experimenting with making my own higher-resolution discs to the BD ROM4 spec with triple-layer 100 GB capacity discs. Triple-layer discs imply two separate layer breaks. Without going into too many details, setting arbitrary layer breaks is important to me so that I can ensure that content encoded for the highest data rates are in the proper physical location on the burned disc.
I don't have any BDXL hardware or TL media at the moment to test this myself, but does ImgBurn 2.5.8.0 support setting more than one arbitrary layer break based on sector sizes?