I used Reaper v4.261 To successfully convert a number of .rx2 files to .wav files
A trial version can be downloaded from http://www.reaper.fm/
Once installed, Go to:
Batch File/Item converter
[Short cut: Ctrl+Shift+F]
A window will pop up - You need to add the files you want to convert into that window by clicking on the "Add" button and clicking "Add Files". Highlight the ones you want...
C:\Cakewalk Content\Audio Library\Loops\Loopmasters\BREAKS DRUM N BASS\DANNY BYRD\REXFILE1.rx2 ,
If you want to save the file with the same name, leave the box ticked that says "Use source file directory". You can also leave the Output format as "WAV" and the "Resample mode (if needed)" as Better.
Enter Filename as: "
$source" (Other wildcards can be used but this is easiest).
Click "Convert all"
When done, go to your directory where the original rx2 files were kept and open it. Your new .WAV files should be in there. Go ahead and open them up in a wav editor such as Goldwave or a Digital Audio Workstation such as Reason.