There aren’t any release candidate for RH5 at the moment. The latest release of RH5 is SR 13, which no longer is a RC.
I see that you have asked a question about Python and a fix for SR 13 but reading one of those threads it looks like you need the layer.py from SR 11. Is that right? If so, the SR 11 version was posted here:
SR12 - Parent Layer Bug?
There is also a link to download SR 11 in that thread (a German version but you can change de-de with en-us to get the English version).