Hi Adeagbo,
Henrik is correct and this is probably the best way to split your model into manageable pieces.
You can also consider using the new
Fluent Code Generation we are offering so that you can shorten the process of creating the initial mapping code with Fluent API. You can then delete the Visual Designer rlinq file and you can continue working with classes only (and maintaining them manually), to avoid the slowness of working with large models.
Kind regards,
Ivailo
the Telerik team