The support for the Rigol DS1054Z is completely broken.
In "Live" mode, triggering doesn't work, meaning that it's almost impossible to catch a data burst.
In "Memory" mode, sigrok always tries to download 3M memory points from channels 1-3 and always gets only 30K points from channel 4, independently of what's set on the oscilloscope, making it, again, impossible to catch a data burst and very time consuming (transferring all the data points).
In "Segmented" mode, it just throws a "Capture failed; generic/unspecified error"
My oscilloscope is running firmware 00.04.04.SP4.
If anyone needs more information like the actual logs i'll be happy to provide them.