Just got home and tried my own PC, is says in my impulse account that I have no products registered so I dont think I will have any problems.
From wha I can remember the first time I registerd with impulse it was from impulse starting by pressing the 'update' button in GalCiv (and I think it asked for a game) but I put in a wrong emailaddress sonever did the activation from the email. Then I registered again but this time I started Impulse manually and I dont think it asked for a game that time.