for the chrome plugin make sure, that you have a dev channel build since we use a feature which isn't yet provided in the stable build. You can get it here
You can also google for a portable chrome dev channel version if you want to use it wherever you are.
Then download the plugin file to your Download folder. Open the extensions page in Chrome (chrome://extensions/) and drag & drop the plugin there. Now follow the dialog showing up and you're ready to go.
Since we need the dev channel, we haven't yet submitted our software to the chrome webstore.
If you use the portable version together with an usb stick to use it for example in an internet cafe, I would create a folder on the Usb Stick (i.e. Encrypted or Temp or something) and copy the .encfs6.xml file from your BoxCryptor.bc folder to it. Now you can donwload single files and put them in this folder. To decrypt them open the folder with the BoxCryptor portable app.
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