Hi there!
If you want to add a buff to a custom parameter, this notetag is the way to go:
<AddCDebuff: paramId/shortName:turns >
Examples:
<AddCDebuff: ra:1;rd:1 >
You can't raise a parameter value by a flat amount using the buff. I'm not in home right now to check, but if I remember well, the custom parameter buffs works just as the regular parameters buff on the editor: You choose a parameter and the number of turns the buff will be valid. I guess there is a hardcoded percent value that is the equivalent to the buff on the rog maker default codes.
In any case, can you copy and paste what you did or show a screenshot of what you did on the notefields?
When I get home I will take a better look into this.

My dynamic template

state applies fine using my skill, but upon going to the status menu where Physical attack is displayed, i get this error

