I came across this thread checking what apps are not compatible with OS X El Capitan and Windows 10. I am willing to switch to BoxCryptor 2.x. I'm really happy with the Classic version and I would like to support further development of the tool. Thus I understand your business reasons you listed in the mentioned post. You are obviously a small company and I think we all know how risky it is to conduct software development business nowadays. So the change of business model is totally understandable and I hope the software will get better with every new release.
But it seems someone made a valid point that these are two different tools. Or maybe a better word - for two different user groups. I thought an upgrade is an improvement not the other way. Let me give you just one example after quick tests with 2.x today.
I have two folders in Dropbox. One contains files which are available for all my devices (Windows, OSX, Linux, mobile devices). I have separate keyfile and password defined here.
The second folder in Dropbox is with different keyfile/password and is used for my sensitive files and is synced/automounted only between my computers. My mobiles devices do not have access to it.
It seems BoxCryptor 2.x allows you to have only one keyfile and password for all your encrypted files with only one drive mapped to it. It's like having the same level of security for all your files and it does not fit reality.
I think the typical user wants to have some of the files unencrypted (because you don't care and you want to share it easily), but some of them you want to have encrypted with different level of security. I personally do not want to keep a keyfile/password on my mobile devices so they can access my financial stuff, but at the same time I do not want to give up on the comfort of having these data synced between all my computers.
How can we address such scenario with new BoxCryptor 2.x release ? Of course you can define new keyfile, but you need to logout, the previous volume gets dismounted and you can log in to the other one.
Is there a way to use two different keyfiles/passwords at the same time ? How to get the same level of security as before ? I'm not sure if it is a good way forward to offer features like sharing an encrypted file for the price of abandoning core features of the application. To be honest I personally can't imagine sharing an encrypted file. Many people tried this approach (even PGP had such functionality) and at the end it did not get appropriate attention. I want my data to be secure, not sharable. If I want to share something I put it into unencrypted Dropbox directory and use its convenient sharing functions. Well, if you want to share something, most likely it does not have to be encrypted ;)
Another thing - what about Linux ? Is there a way to access encrypted files from Linux OS ? Are there any plans to address it? With the Classic version I can easily access my stuff as it uses EncFS.
BTW, I think in order to convince many people to use the BoxCryptor account (not local account) you should really think about two-factor authentication, the best with Google Auth app or something like that. It is too easy to intercept user/password credentials, even if sent over HTTPS.