. in load path
It appears as if "." is added to the load path by isis itself:
[10:55](0)weber@paddy:~$ isis -n
Welcome to ISIS Version 1.6.2-47
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isis> print(get_isis_load_path ());
".:/home/weber/software/isis/1.6.2-47/share/isis:/home/weber/software/isis/1.6.2-47/isis/1.6.2/share:/home/weber/software/slang/2.3.3-24/share/slsh:/home/weber/software/slang/2.3.3-24/share/slsh/local-packages"