Apply same attribute to multiple unique objects

[smpfmc]

I'm really new to Sketchup so forgive me if I use the wrong terminology but I'm trying to solve something that's driving me nuts! I'm using pro version 8 but I've only been using SU for a few months now. My question is: Is it possible to add a new attribute to multiple unique objects in one operation? I know how to add groups of custom attributes to the standard drop down list by modifying the component.js file which helps but it'd be good to take this a step further & create a script for adding attributes to multiple objects.

I'm using unique components to try and record information as something is created (as a record) & found it frustrating that when the objects are not unique & an attribute value is changed the same value was then shown in all objects that hadn't had a previous entry. I ended up making objects unique to overcome this problem. If anyone knows how to overcome this it would mean I don't need an answer to the first part!!

Hopefully I've managed to explain this properly without using numpty terminology!

smpfmc