Why is my touch sensitive switch leaking voltage?
I'm guessing your switch does not have a dedicated neutral connection.  The switch needs power in order for the touch sensor to operate. Without a dedicated neutral, it acts as a high-resistance device and leaks power back over the other hot connector.  With incandescent bulbs, there is not enough power to light them up and you don't notice this, but with LED and fluorescent bulbs, the voltage leak is enough to power them partially. The flashing is due to the ballast. 

The only way to resolve this is to either use incandescent bulbs or replace the switch with a model that has a dedicated neutral connection -- assuming your electrical box where the switch is also has a neutral available.