honestly I didn't understand why Rigol release that crap that they call software
Yes it's a concern of mine as well. I own a Rigol DP832A, DM3058E and a slightly modified DS2102.
Of the 3 Rigol pieces, the only one that I regret buying is the DM3058E multimeter. I really could use the trend function and software of the Agilent 34461A. Even at twice the price, I should have purchased it and probably still will when my wife's looking the other way
I have no intention of returning my 832A. Rigol makes good hardware for the money, but they lack in software. The software is valuable to me as I wish I had the Labview skills/budget to roll my own.
In any case after using the 832A I think it needs two main software functions:
1- To export data from the analyzer function to Excel (preferably not via a USB key as they left THAT connector inconveniently located in the BACK of the unit)
2- A program to edit the groups in the timer function from the PC. Doing it with the 832's key's is like programming a 1980's VCR! It's a real pain in the neck!
Take a look at my Python IVI library. I have some preliminary support for the unit in the abstraction layer, but you can always send it commands directly. I don't have access to a Rigol supply to debug the rigol interface, right now it just uses the default SCPI commands that work with Tektronix and Agilent power supplies - some commands may need to be adjusted for the Rigol unit to operate correctly. The python libraries will run on windows, linux, and osx. There are associated driver libraries (python-vxi11 and python-usbtmc) for cross-platform USB instrument support (no Windows drivers required! Well, you may need to make an INI file, but this is not terribly difficult) and cross-platform Ethernet instrument support. It can also use pyusb for serial communication and pyvisa for everything NI VISA supports. The LAN interface is my favorite; all you need to do is install python, python-ivi, and python-vxi11 and then you can connect to your instrument directly from the python interpreter and send it commands, no configuration required. And you can connect the instrument to your standard home networ so you don't need to deal with a bunch of extra cables going to your computer.
From looking at the programming guide, there are a couple of interesting commands you might want to try. There are measure commands that will read out the voltage, current, and power values for each channel. You could easily call those in a loop to log data and then save it to a csv file, for example. There is also a nice setup for the timer configuration that should be very easy to script. Not sure about the internal recorder, though. There are commands to set it up to record and to load and store files. Looks like analyzer:result? will give you the statistics (median, mean, mode, range, variance).
I'm not sure if they have a command to read all of the recorded values, though. Edit: looks like there is no way to transfer a whole data file in one go, but you can load it up in the analyzer and then call analyzer:value? to read out the values one at a time. Doesn't look like there is a good way to see how many points are available, though. Or to see what the time step is. I would suggest testing out these commands to see how they work as the documentation is rather lacking.