Created an Error problem marker (and accompanying error message) after Refactor > Move action of a Virtual model to a folder under a project

1) Create Relational Model with Table
2) Create Virtual Model.
3) In Virtual model, create Custom Diagram
4) Open new custom diagram and add Relational model to it
5) Save all models
6) Create Folder under project (Top)
7) Create Folder under Top folder (Bottom)
8) Refactor > Move Relational model to Bottom folder
9) Refacor > Move Virtual model to TOp folder
10) Save all and should see both error and Problem Error