I had some problems getting the faber_rebal.R demo to work as well.
First, you have to set the timezone:
ttz<-Sys.getenv('TZ')
Sys.setenv(TZ='UTC')
Second, I could get the following line in the add.rule rebalance to work:
refprice=quote(last(getPrice(mktdata)[paste('::',timestamp,sep='')][,1])),
so I changed it to:
refprice=quote(last(getPrice(mktdata)[paste('::','20140119',sep='')][,1])),
I hope that helps.
Best, Peter