In this case rebuild Your variant and share it under GPL with a different name, let's say "Lizard Sweet Home 3D".
Don't forget the source code with modification specified.
Maybe somewhere in the future, parts of Your code will became part of official version after pass the tests of users and time.
I'm available to test and critic.
----------------------------------------
A computer program does what you tell it to do, not what you want it to do. Murphy's Law
When all else fails, read the instructions. Murphy's Law
If you don't like "AS IS", DIY. Dorin's law
