When registering a custom DynamicContentInboundPipe and trying to create/edit an index the following error shows up:
 

type : System.ArgumentException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 
Message : There are no settings suitable for this pipe type. 
Source : Telerik.Sitefinity 
Help link : 
ParamName : 
Data : System.Collections.ListDictionaryInternal 
TargetSite : Telerik.Sitefinity.Publishing.Model.PipeSettings GetPipeSettings(System.String, Boolean) 
HResult : -2147024809 
Stack Trace : at Telerik.Sitefinity.Publishing.PublishingSystemFactory.GetPipeSettings(String pipeName, Boolean setMappings) 
at Telerik.Sitefinity.Publishing.PublishingSystemFactory.CreatePipeSettings(String pipeName, PublishingManager manager) 
at Telerik.Sitefinity.Publishing.Web.Services.PublishingAdminService.CreatePublishingPoint(String templateName, String providerName)

 

The following is an example of the code used:

CustomDynamicContentInboundPipe.cs
 

public class CustomDynamicContentInboundPipe : DynamicContentInboundPipe
    {
        private readonly IJsonProvider _json;        

         protected override void SetProperties(WrapperObject wrapperObject, DynamicContent contentItem)
        {
            base.SetProperties(wrapperObject, contentItem);
            var mappings = wrapperObject.MappingSettings.Mappings;

            foreach (var mapping in mappings)
            {
                var name = "";
                object value = null;

                try
                {
                    name = mapping.DestinationPropertyName;
                    value = contentItem.GetValue(name);
                }
                catch { }

                if (value == null)
                {
                    continue;
                }

                if (value is IList<Guid>)
                {
                    try
                    {
                        var oldList = (IList<Guid>)value;
                        var newList = oldList.Select(x => x.ToString()).ToArray();
                        wrapperObject.SetOrAddProperty(name, newList);
                    }
                    catch { }
                }
                else if (value is Image)
                {
                    try
                    {
                        var img = (Image)value;
                        wrapperObject.AddProperty(name, img.MediaUrl);
                    }
                    catch (Exception ex)
                    {
                        var a = 3;
                    }
                }
            }
        }
    }

Code to register the pipes:

var modules = ModuleBuilderManager.GetManager().Provider.GetDynamicModuleTypes();

            foreach (var module in modules)
            {
                var pipeName = $"{module.GetFullTypeName()}Pipe";
                PublishingSystemFactory.UnregisterPipe(pipeName);
                PublishingSystemFactory.RegisterPipe(pipeName, typeof(CustomDynamicContentInboundPipe));
            }

There are some Dynamic Modules that are Deactivated. 

Don't take into account the Deactivated modules when registering the custom pipes. 

E.g: 
 

var modules = ModuleBuilderManager.GetManager() 
.Provider 
.GetDynamicModules() 
.Where(x => x.Status == DynamicModuleStatus.Active) 
.Select(x => x.Id) 
.ToList(); 
var types = ModuleBuilderManager.GetManager() 
.Provider 
.GetDynamicModuleTypes() 
.Where(x => modules.Contains(x.ParentModuleId)) 
.ToList(); 

foreach (var module in types) 
{ 
var pipeName = $"{module.GetFullTypeName()}Pipe"; 
PublishingSystemFactory.UnregisterPipe(pipeName); 
PublishingSystemFactory.RegisterPipe(pipeName, typeof(CustomDynamicContentInboundPipe)); 
}