I found this a very strange one too, why give u the button if the boot isn't going to open fully. Now I looked into the boot pop mod and then purchased the parts required via a group buy on another forum. So as standard when I pressed and held the button the boot pops of the catch but through its own weigh kind of latches back on so you still have to use the badge to open it. I then fitted Leon ball pins, fabia struts and scirocco bumpers(which I believe is a cheaper alternative to the ecs tuning kit) then press and hold the button and hey presto the boot pops open an inch which only required lifting slightly to open fully from the boot edge not the badge. It didn't pop all the way open as some have. Then I tried to close the boot having stronger struts makes this slightly more difficult so that isn't great. I decided to live with it and see how it went.
After 2 days of having the new gear fitted the tailgate started to rattle and squeak like mad, nothing I did could help it. So I decided to remove it. Whilst doing this I decided to try one thing so I fitted the original ball pins and struts but kept the scirocco bumpers and hey presto it achieved the same result pops the boot open an inch so effectively it lifts it clear of the latch so u can just lift with one finger and tailgate lifts up. However having the longer scirocco bomber fitted I noticed the boot didn't quite fit flush the tail lights didn't seem to line up properly and this was following the guide from ECS Tuning on YouTube.
So now I have 2 fabia struts, 2 Leon ball pins and 2 scirocco bumper lying in my garage, and when I need to open my boot I just do it as VW intended when they designed the clever system of making the boot badge the boot release. So far it's working out well and the tailgates is back to being rattle free.
My advise would be to forget about the stupid button that looks like it will open the boot and just use it normal, don't buy a boot pop kit there just pants.