I'm in the process of refinishing (re-painting) a wood door. I've cleaned the door with Dirtex and am about to fill small cracks and holes with Minwax stainable wood filler. (I will ultimately fine sand the entire door to rough it up and prime with X-I-M UMA, but that's another day.) I know that the repairs can be sanded once they dry, between 2 hours (shallow areas) to 6 hours (deeper areas). The question is, do I HAVE to sand them AS SOON as they are dry? Stated another way, if I apply the filler today but then wait a day or two to spot sand the repairs, is that OK, or will they be "too dry" or something? Thanks.