If things go wrong... (perish the thought!)

Problems with memory in GT calculations: including segmentation faults with more-or-less informative messages. Try recompiling a 64-bit executable (after a make clean, of course!). On mek-quake and clust, do this by loading or swapping the appropriate module for your favourite 64-bit compiler, e.g. module swap nag nag64, then run make. No need to change the Makefile (unless you want different compiler flags). Might need to run the resulting pathsample on a processor with a lot of memory, e.g. h8gb on mek-quake.