Unfortunately, we have to revoke release 0.12.1 as it turned out that it produces more new problems than it actually solves. Issue #227 seems to need an entirely different solution approach.
New users should therefore use 0.12.0 for the moment. The download links on the homepage have been adjusted.
Users how have already installed 0.12.1 can decide whether they want to keep using it, or whether they want to fallback to 0.12.0. Release 0.12.1 didn’t change anything on the persistence level, so there should be no problems in switching back and forth these minor version. The only difference are changed propagation delays in the standard library circuits of 0.12.1.
Sorry for the inconvenience!