What was the bug that you found?

Those problems were not necessarily with the DNN installation.  Those two issues you mentioned were more likely due to upgrades in the CSS and JavaScript files.  When you viewed the page, your web browser checked for cached files first, and then noticed that it already had a copy.  So, it didn't download the new one from the web site.  It just happened to work the final time you tried.  (Or you performed a hard refresh.) 

In any case, DNN 4.05.05 is a good, stable version to be at.  I currently have portals out there running just fine on both 4.04.01 and 4.05.03 without any modifications.

Without a hitch, huh?  That is always nice.  The more customized you DNN installation becomes, the harder that is to come by.  ;) 

For my most recent upgrade, it took about 3 days of constant tweaking of the upgrade package (adding & modifying files) to finally get it to a point where I could upgrade without a hitch.  (Can you guess how many times I had to upgrade and roll back upgrades on my test installation?)  I have been doing this for about 3 years now, so that is saying something...  That portal instance has many modifications, but the only core changes are in the UserSettings and Default page.  Everything else is custom & 3rd party modules and providers.