Crypt actually should still be available. It is still supported in php7. I'll look into why it isn't showing in the bindings. You could just add the include file and reference the crypt function manually for now.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.