1) Can too much creatnine (or however you spell it when it's metabolized) cause up red flags? I may try to procur my roommates urine (non-smoker for 90 days, VERY athletic and has approx 5% body fat- definitely clean!), but from researching the web, it looks like the creatine he takes for working out may cause an issue.
Whoever told you this is wrong. High creatinine levels are a non-issue because there are no upper limits established for creatinine. As long as the creatinine level is over 20 mg/dL, its satisfactory.

When seeking out a sub donor, nothing has changed - gender is still irrelevant. Just be absolutely sure that the sub donor is completely drug-free (including anything perscribed by the doctor, ot OTC) to minimize any hassles with the MRO. Be also sure that the sub donor had not consumed an abundant amount of fluids prior to giving you the sample..