wheel adapters

Agreed. Just make sure they're hubcentric- to the car's hub, and to the wheel's centerbore. You don't want to have the whole vehicle's weight on the studs alone. The centerbore of the wheel needs to index on some sort of center hub, and transfer the load to the axle/hub. This an example of a hubcentric adaptor (note the raised "hub" around the center hole)...


This is NOT what you want!...
That center register is not the player you make it out to be. A lot of wheels dont have a continuous shoulder to mate with it. Magnum wheels are just one example. The acorn nut is the main player in wheel mounting.
Then again there are many used magnum wheels out there that have their lug holes worn out too. Special nuts were produced for correcting this problem , giving new life to those used wheels.
While working in a trie store we would catch a half dozen per year at most of wheels froze to the center register. Easiest way to conquer it was leave the lug nuts loose and drive around the parking lot. All that says is with loose lug nuts the wheel will eat the center register right along with the lug holes.
Bottom line... correct mating surface contact and tight nuts are the most important factors.