Hey there,
I'm just wondering why there isn't any (Online) Theme Creator for vector maps. I think this shouldn't be that difficult to write a GUI, isn't it?
Maybe isn't, but it's more task for developers of MapsForge, not team around Locus. Btw. I already saw somewhere some editor .. but cannot find it now
Freizeitkarte produces Mapsforge vector maps with two themes for Android. It has a vector theme configurator for its themes: http://freizeitkarte-osm.de/android/en/konfiguration.html