Neo4j sandbox connection settings for Graphileon V3.0.0

Graphileon advises using separate databases for your graph & the schema so I wanted to use local Neo4j (community) for my data & sandbox (enterprise) for the schema but whilst the local Neo4j connects OK I can't connect Graphileon (Version: 3.0.0) to a Neo4j sandbox Recommendations graph. Tried several permutations of settings parameters & found out that the sandbox is "Enterprise" but still won't connect when I "Test Connection".