There is a simple method for ensuring the collisions and layers are setup when starting from a fresh project. After importing the VariaBULLET2D package, look to the menu and you should see the VariaManager menu option available to you with a list of procedures.
What these automated procedures do is safely backup the existing TagManager and Physics2D settings from your ProjectSettings folder and installs VariaBULLET2D’s. This will result in a layer structure and physics settings that you will find in the Manual Setup guide below.
All you need to do is select “Replace TagManager Settings” and “Replace Physics2D Settings” to run the necessary procedures. Once these procedures have completed, you should be able to run all demo scenes without issue. If there are issues, refer to the manual steps outlined below.