To install custom levels into Eufloria, you need to put the level files into the Maps directory, which is in the Resources directory in the location where Eufloria was installed.
To be clear, the following example is incorrect:C:\Program Files\Eufloria\Maps
And this is correct:C:\Program Files\Eufloria\Resources\Maps
Levels with both XML and Lua components should have the same filename except for the extension.
The levels should appear in the Custom Levels section of the main menu when you open it.
We have provided a copy of the main story mode levels as a starting point for you. You can also find stuck threads describing some common script examples and documentation of the Lua functionality we have in Eufloria.
Post back with questions