Thank for your reply
I have already put "Quick Town Styles.asl" (the only style file in the archive) in C:\Program Files\Adobe\Adobe Photoshop CS6 (64 Bit)\Presets\Styles
I draw my roads, select default color for houses, but when I execute "The Town" script, it say "The object style 'Quick Town Road style' is not currently available".
So I don't know what's wrong with my step.
Despite that, the automatic script draw houses along roads very well
And after that, if I want to draw trees, it say the same things with another style missing : "Quick Town Tree style is not currently available".

Thank for your help.