Update: I re-downloaded the .st and .zip and I tryed to replicate your problem, but to no success. I tyed it in Emulation as I have no access to real hardware right now.
Everything plays fine with standard ST 1MB Ram. 512k Ram just hangs behind the language selection (not what you describe).
The only thing that comes close: If I delete the content of the "data" folder, the game hangs on "laden...". pls make sure all files are copied correctly when you create your floppy.