I just tried compiling the current head of the week-of-code branch with new-problem-types-yes, and I'm getting a compiler error:
roblemType_MagneticReconnection.C: In member function 'virtual long_int ProblemType_MagneticReconnection::InitializeGrid(grid*, HierarchyEntry&, TopGridData&)':
ProblemType_MagneticReconnection.C:334:13: error: 'class ProblemType_MagneticReconnection' has no member named 'IdentifyPhysicalQuantities'
this->IdentifyPhysicalQuantities(DensNum, GENum, Vel1Num, Vel2Num, Vel3Num,