Is there a way to select a face in an editable mesh when you only know its index?
When doing it just once, you can quickly type in the Listener something like:
setFaceSelection $ {10}
This selects the face with index 10 assuming that a single object is selected and it is an Editable_Mesh.
If you are doing this very often, the following macroScript provides a UI with a spinner to select the face index and some error handling:
SCRIPT
macroScript FaceByIndex category:"MXS Help" ( global SelectFaceRoll try (destroyDialog SelectFaceRoll) catch() rollout SelectFaceRoll "Select Face" ( spinner face_index "Face Index" type:#integer range:[1,100000000,1] on face_index changed val do ( if isValidNode selection[1] and classof selection[1].baseobject == Editable_Mesh do ( if val <= selection[1].numfaces then setFaceSelection selection[1] #{val} else setFaceSelection selection[1] #{} ) ) ) max modify mode try (subObjectLevel = 3) catch() createDialog SelectFaceRoll 150 30 )--end macro