Explicitly compare compositionCheckpoint against null, since it can be 0
Explicitly compare compositionCheckpoint against null, since it can be 0

andrewleverette/atom,atom/atom,Mokolea/atom,Arcanemagus/atom,liuderchi/atom,atom/atom,kevinrenaers/atom,brettle/atom,ardeshirj/atom,PKRoma/atom,Mokolea/atom,andrewleverette/atom,t9md/atom,t9md/atom,t9md/atom,Arcanemagus/atom,ardeshirj/atom,FIT-CSE2410-A-Bombs/atom,kevinrenaers/atom,brettle/atom,Mokolea/atom,PKRoma/atom,liuderchi/atom,atom/atom,Arcanemagus/atom,kevinrenaers/atom,stinsonga/atom,stinsonga/atom,FIT-CSE2410-A-Bombs/atom,brettle/atom,FIT-CSE2410-A-Bombs/atom,stinsonga/atom,stinsonga/atom,andrewleverette/atom,PKRoma/atom,liuderchi/atom,liuderchi/atom,ardeshirj/atom