There is surely a bug loading multi-object objects (an object consists of several aligned sub.objects) in Bambu and therefor Orca as well.
When I load a precut 3mf in BambuStudio everything is fine (exported from Fusion360). But if I then save this as a project and reload it, it often happens that the objects are not aligned anymore or that part of the geometry is wrong.
Related to 3mf-files itself - I think there is still a long way to go. Consider that a 3mf-project from Bambustudio even silently was not loading in PrusaSlicer 2.5 before. Only with 2.6, it recognize that it is a project file from another slicer and loads geometry only. Heck, even most designer still publish as stl-files and not as an 3mf-file. And Cura for example ignores the ‘names’ of the sub-objects. And all slicer currently ignores the measurement of objects (ie. ‘mm’),
So in the end - yep, for the time beeing seems like repainting is the only way to go.
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