I lost 4 million xcn for that ridiculous backup function in qt. Software. I created the backup, and sure of what the software does, saved the file in two different places. Now that I go to use and import it back, it shows a .dat.url file which is a simple text about nonsense.
So 4m xcn is gone, I know that I should have checked it before, but, to be honest, the pace of the reference software development has been ridiculous. I asked for the web-based wallet for several months, but nothing..
The main dev catia disappeared for several months, and all the core developments relies on him.
Of course bitfreak and catia have the right to choose how to spend their time, they have no obligation to continue developing xcn persistently, but what remains is a red flag  for anyone who is interested to invest in xcn long term.
No matter how innovative and ideal a coin idea might be, it will not last long if not supported by continuous persistent development, as an organic live existence.

ps: I know about the loss for a week now, backup has been saved in early April. I am not much angry about the 4m xcn loss.  As a veteran investor I've got much much more from the cryptocurrencies than what I lost here. But as one of the earliest supporters of this project, following it since it was only a paper 2 years ago, I have to criticise the naked facts.