Evan Duffield has responded to a message that I sent to him. Loosely interpreted and summarised, the tone of Evan's response is exploratory as to what the Dashcoin Community wants in order to resolve the dispute between Dashcoin and Darkcoin/Dash. I have sent copies of that communication to prominent members of the Dashcoin Community.
With regards to an action of 'Passing Off', I would advise against that for now. Whilst there may be some merit in it, such actions are time consuming and can take years to complete, with the losing side often having squirreled away all assets to become a 'Man of Straw'. Claiming costs and damages from a 'man of straw' is not a good outcome. To my mind, the Dashcoin Community have far more effective weapons at their disposal with which to protect their interests. For instance, putting in an objection to all applications for the trademark 'Dash' in the class that covers electronic currency on the ground of prior use.
If Darkcoin/Dash succeeeds with their trademark application, it could make life difficult for Dashcoin. Intellectual Property Offices worldwide seek out examples of prior use when an application is made to them. They should be made aware of that prior use by the Dashcoin Community as soon as possible.
It would be useful to find out what the Dashcoin Community wants. A preliminary option appraisal might consist of:
Option 1. Do nothing. Always an option.
Option 2. Stop Darkcoin/Dash from using the name Dash.
Option 3. Accept some form of a buy-out compromise. This could involve a direct payment as a community member with an adjustment for the amount of Dashcoin held.
As a community please let me know what you want. I will help in any way I can.