Absolutely. The powers of Transit Police were not changed, neither were the Rail-related pieces of legislation. They can still only issue fines for offences under those acts.
The Smoke-free Environment Act 2000 was what was amended, to both extend the coverage of public areas, and to add the authority of Police to issue fines. Read the act here:
Smoke-free Environment Act 2000. Sect 14 and 14a lists who can enforce the act. Sect 14a was only added in Jan 2014.
This article describes the limited powers that Transit Officers have.
This does not mean that there are
not fines for smoking on railway stations, only that Transit Officers are limited in where they can enforce them. Police can, and do, issue fines for smoking anywhere on Public Transport related infrastructure.