actually i pretty good with biological sciences.. and after looking into it myself, i've found that the #1 effect of creatine(or the most useful), is for it to donate its extra phosphate molecule to used ADP to convert back to very very useful ATP! this is crucial to get that extra rep @ the end of a set, and it definatly intesifies work outs.. and as long as taken with simple carbs(sugar), it will be moved into your muscles aprox. 30 min after ingestion(powder)..
my 2 cents! anyways i dont think there is a wrong time to take creatine, except if it has sugar(dont take it before bed).. mostly just preference