removing a dynamic type?

This is just a guess...try removing it from the PersistenceManager (including query cache).  RemoveEntity, maybe?  This is a good question.

The key to manipulating the DGVBM in code is to add a ViewDescriptor (IdeaBlade) to the Descriptiors collection...not a DataGridViewBindingDescriptor (DotNetControl).  Hopefully, IdeaBlade will include an example of this in their next release of the tutorial solution.  I have an example if anyone is interested.

The Type itself that you've created cannot be removed from memory (or really more correctly from the AppDomain), but you can, in some situations, modify the columns of the corresponding EntityTable.

// Get the table out of the PM

EntityTable tbl = mPm.GetTable(myDynamicEntityType);

// Modify the table

tbl.Columns.Add("NewIntCol", typeof(int));

//Optionally reset the prototype table

EntityTypeInfo.SetPrototypeTable(tbl, "");