I have made several testings on my personal site with different Adobe Muse Versions.
After converting my site from version 2017.0 to version 2018.1 I have several issues.
1. The stroke settings will be changed from inline to outline or center for many many page elements. Very annoying.
2. The links get broken on the web page as soon as I start editing or changing something on the master page
3. Pinned objects on the master page and the web page are causing a lot of trouble. Pages get broken.
4. Master pages with pinned objects cause a large white gap on the bottom of my web page for some reason
5. Aligning objects by using smart guides is still a huge issue. I have to zoom in endlessly to precisely align objects.
Even in the case if the objects have the exact same width and heights. Smart guides are invented to save web designers
a huge amount of time and to make sure the elements are 150% correctly aligned. I don't want to spend endless
hours and hours and hours to align objects properly on a simple layout.
Adobe has a LOT OF WORK to do for the next update with their extended Muse product support till 2020.