Yes, cleaning them is a MUST! All the tires I've ever glued had a brownish film to them. Make sure the tire bead AND rim are clean.
I like to use fairly thin CA because it will wick around the tire for a better seal. If the glue is too thick, you get "clumpy" spots.
No matter what you use, they will eventually come apart if you spin them so fast that they look like pizza cutters.
All this makes me wish you could just get tires like regular tubeless inflated car tires, except fiber belts instead of steel. I know it may make the cars bouncier, but I don't care.