Your getting some good advice here, but IMHO you will probabaly ruin your canopy if you try to dissolve the CA with anything.

As a couple of the pro builders said, you gotta sand it off.

The only thing I would add, is to use a small (3/4 x3/4 inch) block of hard maple, as a little sanding block. Get right over that drop and with fairly light pressure, wet sand it off. If you press too hard you will raise the CA bump by pushing it down while sanding.

After than you will have to go up to about 2000 grit before you clear it. This can be done locally, right over the spot but of course the clear will need to go over the whole canopy. I am not sure if the polishing technique David is describing can be done in one spot as I have never tried it, but I have definitely done what Harley is describing.

Good luck.