When entering classic palm watch out for your thumb, it will naturally do a suspicious movement that can be detected even with good misdirection. A good way to remove that is by very gently and naturally having your thumbtip and indextip touching eachother, this will make sure the hand stands still. Also remember while in classic palm, even though you have the ability do stretch your fingers and show it empty from the back, your fingers have a natural curl to them.
Security will come in time, and can be helped with some moist (good practice is to wetten your fingers and try to classic palm it and hold it there, it's a challange but rewarding).
Keep the work up mate, remember to use the Coin Magic forum as soon as you need any help, it's quite a solitude but as soon as topics comes up you can expect replies.