Well I think its a well known bug (even reported on github), that when you try to make some wooden floor with VE Arche woods (Birch, Mahogany, Walnut, etc) the floor bugs and thinks you need to use VE Arche dummy called by the name of the wood (ie.: Birch or Walnut), and then you cannot construct the floor.

Maybe a workaround should make the mod consider using both this and normal wood.

Im just pointing out since its a well known bug reported here and on github, and its a little detail that if corrected will enhance even more the mod experience.

Best regards