"Measurements Fail with Math On" bug, then I'm going to update.
i've tried to reproduce the "statistic measurement freeze failure during math on" bug, and "zoomed time activated, change persistent and brick the scope" bugs on SP2, they are not there anymore. whats a bit annoying is the slower respond time, but thats not a big deal for me as quick scroll still be reflected in the GUI albeit the slowleness... and i found trigger failure weirdnessness bug probing CAL signal https://www.eevblog.com/forum/testgear/rigol-ds1054z-unable-to-trigger-cal-signal-at-lt-0-6v but afaik its not happening on the other external signals, and i'm not sure if this is specific to SP2, this probably also happening in the older FW.. imho this high resolution FFT in SP2 is far outweigh any older (or probably newer) bugs, just stay away from them, i havent encounter anything serious so far, but there is another thread to report such bugs... ymmv.
When I reported the Measurements Fail bug to Rigol USA, they were immediately able to see it on their test scopes with the SP2 firmware, and agreed that it was a bug. The problem with reproducing this bug is that it happens after a totally random time interval, sometimes it will hit within seconds and sometimes it takes 30 minutes or more. It is definitely there though. I don't know why you can't see it on your scope. Lots of other people have also seen this bug with the new firmware. The workaround is to keep the Math trace set up, but turned OFF, when you are using measurements, and only turn the Math ON for a brief time when you need to see what it's doing. It still might bite you though, since sometimes it only takes a few seconds for the bug to hit.
As far as the Freeze bug goes: when I tested both my old scope running Boot Version 0.0.1.2 and the new scope running Boot Version 0.0.1.3, both running the latest SP2 firmware, the old scope still was able to freeze, the new firmware made no difference at all for this bug. I had them both for three days before I returned the "freezable" one to Rigol, and I tested them side-by-side (actually one on top of the other) on my bench. The new firmware apparently does _not_ fix the freezing issue on scopes that have Boot Version 0.0.1.2, as far as I can tell. The workaround for those who have this bug is to be very careful about using Persistence and Zoom at the same time.
The SP2 firmware also introduces the "Pluses" spelling error and sometimes the "pluses" counters and edge counters miscount the actual number of pulses on screen.
No workaround here--- just suck it up and ignore the spelling error, and count your pulses by eye to see if the counter is off-by-one.
And of course it makes the scope very slow to respond to some controls, like especially the channel vertical position controls. So use "safecracker mode" on your fingers and turn the knobs slowly.... very slowly.... and wait for the scope to catch up.
But your problems with trigger level are something else. As I posted at the time it was being discussed, my scope has no problem triggering on the Calibrate signal down to smaller voltage levels.
The FFT does seem to work better now though.