Wow, this issue is so old that I've even disabled notifications for this topic (hence my late response). That being said, I did not receive any communication from R- recently, so I don't know what's happening with this.

With that kind of attitude you'd be lucky to get anything more back. R- has already defaulted on this, so it'd be to your benefit to just get as much out of this as you can. One idea of what you can do is to send him an offer that gives him until a set date to pay you back at a discount, but on the condition that if he fails to do so he'll owe you even more than he currently does. Give him a limited amount of time to accept this offer. As a show of good-faith, it would be nice to at least make an offer like this once.

Of course, if you and R- come to an agreement, we would be happy to remove R-'s scammer tag.