Beta 3 doesn't allow to rename resource files such as layout files. It does show the renaming dialog, but when trying to apply changes it reads the following error message:
Refactoring cannot be performed
File .../myapplication/R.java is read-only
Also I have Beta 2 version in a neighbor directory and renaming works perfect. Any ideas how to fix that?
UPD: I reported the bug (#65079508), and now it is marked as a duplicate of 65032914 https://issuetracker.google.com/issues/65032914
So, the issue is even wider and if I understand it well the bug will be fixed in some coming version of the Studio.
UPD#2: Beta 4 is released. The bug is still not fixed.
UPD#3 Fixed in Beta 5.