Yes.
All objects like dynamic blocks, multileaders, etc are shown as proxy objects (unnamed blocks). Constraints are ignored, objects can be moved or edited.
When opening the drawing in AutoCAD again, all objects are the same as they were, so a dynamic block is dynamic again, even Civil3D surfaces are surfaces again. After a regeneration the constraints are applied as well so an edit on lines in BricsCAD is corrected in AutoCAD.
Only a weird thing: if I save a drawing in AutoCAD in v2010 format, it will be (for example) 1MB in size. I save the same drawing in BricsCAD in v2010 format, then it is 750KB. when I save the same drawing in AutoCAD again, it is around 1MB again. I really wonder why AutoCAD needs more space for the same stuff.