Lispworks IDE free version seems like the safest bet for a beginner recommendation. It works without fuss, it has a GUI step debugger, is well supported, consis

Lispworks IDE free version seems like the safest bet for a beginner recommendation. It works without fuss, it has a GUI step debugger, is well supported, consistent across platforms and architectures. All those things outweigh the limitations of the free version for newbies IMHO.