There should be no reason you can't take a backup and restore it over a new database then copy the existing code. Just make sure you change your connection string and any references in the site settings to point to the new website.

Regarding BS3, the CKEditor does some auto formatting so don't rely on the users to get things right OR that the CKEditor will leave what the user enters alone. For instance I've seen tags with no value in side them and the CKEditor removes them and I know the BS3 uses things like that for icons and such.

Good luck
Brenden

Regarding having two versions... there could be licensing issues there if you are running both environments under different domains. Maybe someone at Kentico can issue you a development license.

Regarding BootStrap 3.... I personally found it would not work on a site I was recently working on. I gave up and implemented it in PHP really fast and it turned out awesome. Like Froggeye said, I was running into all kinds of issues both with .Net itself and with Kentico, stripping out attributes, etc. I am sure it is possible, I just couldn't spend more time on that project because of deadlines.

good luck!

I've designed a few sites in Kentico with Bootstrap 2 and 3 and have had very, very few problems. Since it's just a CSS library with some jQuery plugins throw in, it's really easy to make adjustments if you run into any issues.

So far, the only big issue I've run into is with jQuery and Bootstrap 3. Bootstrap 3 requires jQuery 1.9, but for some reason including 1.9 messes-up Kentico's UI, which is built on 1.7.2. Most of the plug-ins will still work with 1.7.2, with the exception of the carousel plugin - and maybe others. However, I've read a few workarounds in the forum that seem like they will fix my issues. I just haven't had time to work on them yet.