Openelec 6 is in beta testing at the moment and once fully stable you system will update automatically as long as you have auto updates on in your openelec settings. This update will bring kodi 15. If you really want it now check out the openelec wiki and you can download the beta test version and manually install. Personally I will wait till the stable version is out.not 100% sure but I think kodi is embedded in openelec so to get 15.2 we will need a new update of openelec, but I would not worry about it too much Ive not noticed any difference between 14.2 and 15.2
Just to keep the thread up to date, the latest openELEC update has returned the VPN configuration entry to openELEC's Settings. See https://droidbox.co.uk/blog/t8-s-ota-update-for-openelec/
Sorry for the delay, can you let me know what sort of update you're looking for? If you've not set up a VPN connection previously, http://support.purevpn.com/openelec-how-to-configure-pptp runs you through the basics in openELEC.Any further updates on this?