Did you refresh MxModel reflection?
I refreshed it.. still not showing all the associations. It is showing all the association which are owned by other entities and referencing the target entity like . anyEntity_Entity1 for the above mentioned example
But it is not showing any assocations which are owned by Target Entity like Entity1_anyEntity (these type of associations were not shown there)
In such situations, the workaround is to use many:many relation. Then, you can make bidirectional reference, where both entities are owners, and it will be possible to "navigate" from Entity-2 to Entity-1 and vice versa.
Of course, the downside is that you have to add logic to make it "one:many" in the application. For example, in company:employee, to make it one:many, prevent association of more than one companies to one employee through form validations, or Before-Commit event handlers.
May be not the right sollution, but I also have found that the restrictions that are set on the selections where a bit to strict in some versions of the Excel importer. You could simply remove the restriction from the select forms (remove the contrained by). There is a drawback though. These restrictions prevent you from easy mistakes. When you can select anything, you can also select things that are simply not possible. The result would be that the import will not work.