You can't fade between presets using DMX timing from the cuelist on the console.
So your current method of intensity at 0 is correct.

To see any fades between presets - you would have to apply timing to the relevant parameters in the presets IN CATALYST
Then when the preset is triggered by DMX you will see a 'fade'

However - it depends upon the content of your preset...
Changing between a curved mix and keystone mix is not a fadable attribute...
but changing the keystone value of that curved or keystoned mix is...
(and obviously most layer attributed are fadable)

Alternatively - if you have a hog3 - then ignore presets in catalyst - and just program your show using the full capabilities of the DMX console to control the layers and any mix parameters required...!!!

S