Hi,
if you know how to program php/mysql, then within playmaker it's very easy, you simply send a url with GET variables using wwwObject action. and you can get info back into playmaker using the same action and store the returned text into the variable "StoreText".
I have some UniWeb custom action cooking as well as Json parser, but it's not yet ready for this forum, pm me if you need them.
bye,
Jean