You might try a few things.
1) How long is your recoil spring? A worn/compressed recoil spring is short enough to fit inside the slide with little to no compressing. Both of my 82s were unissued and the recoil spring is an inch or so longer than the distance from the breech face to the muzzle. A worn recoil spring results in more felt recoil due to higher slide speed during recoil and can be perceived as trigger slap. You can get recoil springs from Wollf at http://www.gunsprings.com/Semi-Auto%20Pistols/CZ/82%20%26%2083/cID1/mID16/dID92
. The 16lb spring is best for stock 9mm Mak ammo.
Another way you can tell is by how far your 82 throws the empties. Mine drops them pretty much at my feet. If yours is throwing your empties more than 10 feet, the recoil spring needs replaced.
2) You can place a piece of silicon or rubber behind the trigger. The best material is the self-adhesive rubber feet used for appliances and such. Just slowly file/sand the rubber down until the trigger breaks but then stops its rearward travel. It must reliably break though. It is better to remove a little too much than to pull the trigger and nothing happen. I have done this with some of my ultra-compact pocket guns. The recoil is so severe, the trigger slap is brutal.
3) You can also recontour the face of the trigger with a fine file. The only complaint I have with the 82 is it's sharp edge where the face meets the side of the trigger. Softening this transition can reduce trigger slap as well.
I hope these suggestions give you some options. Number 1 is the most likely cause of the trigger slap you mention. Let us know how things go.