New source code available on GitHub, a bug fix you can apply as a plugin - it patches a database function that can sometimes fail with Sql Compact if the length is over 4000 characters - this plugin attempts to bypass that by just throwing away the Sql Compact error and continuing.
https://github.com/marc365/nopCommerce-SqlCe-Patch
there is no need to install it, just upload it to the Plugins folder and restart the application.