Clean re-install of Dorico 4 Pro

The initial upgrade to Dorico 4 Pro went almost smoothly (though, I did have to launch eLicenser twice).
Yet, from the very beginning I’ve noticed couple of strange things: even the most common actions - e.g. switching from Write to Engrave - took noticeably longer time in comparison with Dorico 3.5.
(Clarification: my educational projects have typically 2-4 flows and the instrumentation is typically 3-5 players.)
Another puzzling thing was the file size change(s). Even minor changes resulted in dramatic size increase in project file size - e.g. from 1-2 MB to 3-4 MB.
After a few days I started seeing proverbial beach ball quite often; even on starting Dorico with no project being selected.
Considering that no similar complaints have been logged in the forum, I assume that something went wrong with my installation of Dorico.
So, here’s my question: what is the most certain way to cleanly re-install Dorico 4 Pro. (I have no problems editing files in Application Support directory)
My machine: Mac Mini 2018 3.2 GHz 6-Core Intel Core i7, 16 GB 2667 MHz DDR4
Igor Borodin

The increase in project size and in save time in larger projects will be due to Dorico now saving PDF and PNG thumbnails in the project (both to display in the Hub and for future use with e.g. a Quick Look plug-in on macOS). You can disable this on a per-project basis in File > Project Info.

I don’t think you need to worry about reinstalling Dorico 4. It sounds to me like your installation is in good working order.

Thank you Daniel for prompt response, clarification and re-assuring. Will follow your recommendations.
Looking forward to ‘maintenance’ update (There are some minor (inevitable/natural for the app of Dorico’s scale) kinks.
Never could understand the usage of the expression “It goes without saying…”. Nevertheless, can’t help saying: "It goes without saying: “Bravi” to your team.