Good question on what would be the proper doseage. If a 5 gram oral dose gave a measured blood level of ~2.4 uM from the paper Maxwatt referenced and a 100 mg dermal dose that I calculated gave a ~88uM dose, then you should need to really scale down your doseage. 50-100 mgs should be plenty for everyone.
I tried the DMSO, I think the spray bottle is the way to go. I just had a small bottle of it and tried to drip it onto my arm. Very messy way to go and its feels oily (DMSO is a high boiling point solvent). I sprinkled ~100mgs on it, it covered approx. 1/2 my inside forearm by the time I spread it all around. I had to drip a little more DMSO on as all the t-res did not go into solution right away and made more of a paste. Again, I think its just the messiness of my method of application. 10-15 minutes later, its all gone. Some small white powder marks at the edges of the original DMSO smear which I take to be t-resveratrol that did not get into solution but the rest of my inner forearm is clean and no signs of dermatitis (skin irritation).
The spray is the only way to go. That's why I got the spray bottle.
It also happened to be the one that was 30% aloe, so that appealed to me.
If you spray in the crook of your inner arm and let it puddle up a bit and
put the powder in there, it will melt in. 50-100 mgs is a very small amount of powder.
If it doesn't all absorb, just spray a little more dmso on it.