Photoshop Plugin with License Key

Hi,

I want to hire a developer to build a plugin for my Photoshop resource website.

I have a couple of questions and I'm hoping they can be answered here

1. Is it possible to license key plugins for Photoshop (so we/I can control their use)
2. Is it possible to push assets to a plugin from a web server - i.e push new packs of graphics like textures etc and have them automatically available inside the plugin by the userclicking"update" or "refresh" on the plugin

3. Where do I hire a developer that can build Photoshop plugins?

Thanks,

Adam