The problem that will arise when using baby powder will be found when one starts to apply the trim colors, and when removing the tape (even low tack), the entire base coat can and will lift off in areas, what causes it? scented oils used, if talc is going to be used use unscented, cornstarch, microballons, chalk are probably better choices, but even then, do not over apply these fillers, as they do weaken the way that paint sticks to the surface, easy does it!