If you have a non-permanent ID with R (Right to land), you can just use the ID to enter Macau.
No, the letter indicating your immigration status:
A = right of abode
R = right to land
U = unconditonal stay
C = conditional stay (i.e. you have a visa of some sort)
The letter at the start of your HKID number doesn't generally indicate much except, roughly, when it was issued. For about the last 10 years the first letter has normally been R, before that it was P. FDHs are an exception: their HKIDs generally start with W. And there are one or two other special cases as well I believe.
Last edited by Gruntfuttock; 05-07-2013 at 07:16 PM.