1) There is really no need to update the webassist folder after updating the extensions, the updates made are in how the extension works within dreamweaver, not to the code that is generated in the helper files.
2) No, there should not be a problem, The version number in the MXP was not updated when it was built, but the files that it installs are the 1.1.0 version. I have forwarded this to our webmaster, a new build will be created to correct the version number, but in reality, you should be fine.