I would like to share how I got the correct answer to #3 on the 2022 qualifying exam. I set $MaxPiecewiseCases to 10000 and then
\!\(
\*SubsuperscriptBox[\(\[Integral]\), \(0\), \(2022\)]\(\((
\*SuperscriptBox[\(x\), \(2\)] - \[LeftFloor]x\[RightFloor] \
\[LeftCeiling]x\[RightCeiling])\) \[DifferentialD]x\)\)
worked to output 674.
Edit: I didn't realize I already solved this in my first post.