The new 3.1 Modeler does not show DbEntities from other DataMaps in the same project. This worked in 3.0. Steps to reproduce:
1. Create a project with 2 DataMaps and some DbEntities in each DataMap.
2. Create ObjEntity in one DataMap.
3. Table/View dropdown will only contain DbEntities from the ObjEntity's DataMap. (compare this to Modeler v. 3.0 - it will show DbEntities from both maps)
A similar scenario is targets of DbRelationships.