Hi. Can you check a few things in your database. I am checking on v2.2 and I see that is should be set to nvarchar 4000 which should be plenty.
Table: DynamicForms_Events
Column: DynamicEmailMessage
Also check these stored procedures:
DynamicForms_AddDynamicEvent
DynamicForms_UpdateDynamicEvent
This would be the first place to check. Make sure everything related to the DynamicEmailMessage is set to 4000 nvarchar.
This should be plenty, if more is needed you might need to change the column to be text instead of nvarchar. We have not needed to do that yet for most implementations but we will review it and make the change in the next release if its needed.
-Chad