I have heard nothing so far, but unfortunately I have some bad news as well:
More playthrough found some bugs with the multi romance "fix". It triggers the initial conversations started by Amber on many occasions. Not as often as to make it unplayable, but often enough to break immersion for me. I have checked the variables in use in the script, and they should NOT trigger as far as I see. The conversation started was triggered by 2 global variables, which did not have the values needed to trigger it when i checked them in a save game. The only conclusion i can come through is that the multi romance patch in Bg2tweaks messes with one of these variables as well in runtime, and such triggers the dialog.
I have been running (and modifying) both Fade and Amber NPC mods, and after more testing i decided to uninstall the Amber mod for now. The script is much harder to get an overview of in Amber than in Fade in my opinion.
I have Fade working with multi romance now, and also have the npcflirt mod and Romantic encounters mod working with multi romance.
What i have done for all 3 mods (fade, npcflirt and RE) is change the script and dialogs that set the global romance variable for for that perons to 3 (meaning the romance is over). They now set a bogus variable to 3 instead, one that is not used anywhere, keeping the actual romance global variable for that person as is. For instance a dialog option setting "JaheiraRomance" to 3 now will set "JaheiraRomanceXX" to 3 instead, leaving the existing "JaheiraRomance" variable as it was before the dialog.
This means more than multiromance, this also means dialog options that usually lead to you picking one or the other or even dismissing one or the other, will NOT stop or hinder the romance. So all the women are now very persistent and dont give up on you QUITE so easily, but you still have to earn their affection just as much as before
BTW, If you just want the sound fix for Amber mod, that is easy to fix and will work flawlessly (it is just a change of an install parameter, nothing in the scripts of the mod).