Hi guys,
actually you can, but you need an account on SAP Service Marketplace 
.
Here you can find different (not all) revision of HANA Studio.
For more details, have a look on this video.
Bye.
P.S. Honestly I have never faced any problem working with a "more recent" revision of the Studio - for example Server rev. 1.00.39 and Studio rev. 1.00.41.