Version 2.32 is the latest version.
As NJDude already said, the RandomAccessFiles library is part of the 'standard' libraries and shiped with each new version if B4A.
This means, that, when you unpdate B4A, you get the latest vesion of RandomAccessFiles.
To use it, you still need to check it in the Lib Tab in the IDE!
Make sur that you don't have in the AdditionalLibaries folder.