Is there a way to read r-code?

If you google around you will find a "de-compiler" for r-code.  It is offered as a service, not a product and one is required to prove that one has the rights to the source code, i.e., someone who only has r-code in the license from their vendor will not be serviced, but someone who does their own development and was just especially careless will.  It is not free.

And, be warned that the tool was developed for a much earlier version of Progress and is unlikely to work very well for code using features in recent versions.  Moreover, the results are understandably crude since a lot of the "pretty" features of the original code are compiled out in the process of producing the r-code.  I.e., it is not uncommon that it is as easy to re-invent the missing code than it is to de-compile it and get back to a maintainable piece of code.