Hello,
DualSub 1.1.0 requires connectivity to work. Otherwise, the splash remains forever (this a known bug, I will solve it in the next version, 1.2.0).
Recently I finished the online questionnaire that DualSub 1.1.0 was checking in the startup. Maybe this is causing this side-effect in your instance of DualSub.
In order to solve your issues, at this moment you have two alternatives: downgrade to DualSub 1.0.0 or wait until DualSub 1.2.0 is released (I am working on it but I cannot know when it will be completed).
Kind regards,
Boni