When upgrading from Entity API 7.x-1.0-rc1 to rc3, one of our rules, using Rules module, that adds a link value using 'Set a Data Value' to a link field upon updating a node and viewing it just plainly stopped working. We've reverted back to RC1 for now and will keep an eye out for it to see if the new version will work. As of now, we have no output errors or reports, only the fact that once we took our backup sites and upgraded from RC1 to RC3 on three different backups for three different sites, we replicated this occurrence every single time. I can not speak right now for RC2, but will likely try it out just out of plain curiosity and report back to you.

Thanks,

Lee Quessenberry