I just updated to 4.18 and got the latest github version of the RMC. It failed to compile, because there seems to be just a small error, probably just a typo or sudden API change I would guess.
In RuntimeMeshComponentDetails.cpp, on line 28,
SelectedObjectsList = DetailBuilder.GetDetailsView().GetSelectedObjects();
Should be changed to:
SelectedObjectsList = DetailBuilder.GetDetailsView()->GetSelectedObjects();
In order to compile properly. For some reason the pointer returned by GetDetailsView() wasn’t being dereferenced.