When building the Model from the Syncfusion sample, downloaded from Github, I get the following error:
Index and length must refer to a location within the string
https://github.com/SoftFluent/CodeFluent-Entities/tree/master/Samples/SoftFluent.Samples.Syncfusion
I did install the pre-requisites including the WPF components from http://www.syncfusion.com/products/wpf
Additional Information Added After Initial Post of Question
I isolated the error to the Syncfusion WPF producer. When I disable the producer the error goes away. I tried re-compiling ContactManager.SyncfusionProducer.dll and placing it in C:\Program Files (x86)\SoftFluent\CodeFluent\Modeler. I got the same error.