There may be a need for these to operate slowly. I don't do programming, but I've always presumed that clicking on "Bracket Results" causes a calculation of every bracket to take into account new scores is being done/initiated.
I have a 28-team four-player match point league and those items open slowly. In my 4-team three-player league, they open quickly.
Not being a programmer, my best guess is that the size of the league and its complexity may be a factor. Bracket Registrations, for example, has to pull up a roster of 112 regular members plus ~40 subs, and if I insert a sub onto a team, that needs to update itself for the bracket registration screen. Ditto for the Bracket Results, because it initiates a calculation of everything. But with my smaller league having very few members, those things don't take so long.
How large is your league?
Always check, download, and install the most recent update of your software to ensure that issues may have been corrected.