In case this helps anyone else ,I have successfully setup SSL VPN from a chromebook to my DrayTek Vigor 2762 using instructions in the following on-line post by Steve Tomalin in Google's Chromebook Central Help forum:

https://productforums.google.com/forum/#!topic/chromebook-central/QZrhsTu2X1s

Firstly you need access to the Android Play Store on the chromebook so you can install the DrayTek Smart VPN Client for android.

Next in the Chrome browser , you need to open the url: chrome://flags#arc-vpn

When this url is loaded , change the value to "Enabled" and reboot the chromebook a couple of times.

You can now run the DrayTek Smart VPN Client and configure it to connect to your Vigor router( Assuming the router supports SSL-VPN)

Once connected you now have access to the remote LAN resources from chrome apps as well as android apps on the chromebook.

Thank You for your assistance

Just setting up 2762 this evening and then update the Chromebook

Paul