The game is unfortunately way too big for a 48k machine. You could play this on a 128k Speccy, but only if you own a divIDE or divMMC device with esxDOS. Bob Fossil ported ZXZVM to esxDOS. So in case you do have a device like The Future was 8-bit's divMMC Future for example, just drop the ghosts.z5 file on the card and then launch it via ZXZVM. Here is some information about it and how to set it up https://spectrumcomputing.co.uk/forums/viewtopic.php?t=6169