I’ve used a few of the Light My Bricks kits and I will rate this one as one of the toughest to install. It’s got nothing to do with either the LEGO set or the lights kit, it’s just a combination of complex light positions and lack of places to hide the cabling.
The instructions to install the lights are a little vague but if you have a reasonable amount of knowledge of the set and LEGO experience you can get through it.
These lights really cannot be installed until the kit is finished being built, but you will have to pull apart a few bits if you want to have the complete hidden cable effect for your Treehouse.
Don’t rush the install. Take your time and think through your cabling routes before permanently attaching the lights with the stick pads.
As a product 100% love the effects achieved, just need to work on how to hide the cabling better.