1) You can check the data logger voltage and internal temperature after you imported the RWD files into the data base. After importing, just open the site file NSD in Microsoft Access with reading option only and without converting the data base? There should be a table VoltsTemp with the information you want from the data logger. You can also get access to this information using Excel, but the steps are different depending if you have a more recent version of Office or not.
2) Regarding the iPack status, you can check the voltage at the comminication time that was configured in the iPack in the SDR main screen. If you installed the SCM card that comes wiht the iPack in one of the logger annalogue free channels you can check the 10min batery charge as if it was a sensor. Usually you show see the voltage around 12V and when the sun appears the voltage rises to about 14V and stays there until the sun sets.
I don't know if it is possible to check the iPack error codes, but if you say you are receiving files it may be a problem with the cellular signal where you have the mast. You must be aware that the iPack will send full files only, if it is having poor signal. e.g. If you 1 daily communication, the iPack sends the full file of the previous day and the partial file of the day of communication from 00h00 until the communication time. If it is communicating every 2 days you get 2 full files of the previous 2 days and the partial file of the day of communication from 00h00 until the communication time. The same happens when communications are temporarelly interrupted.
I hope this information helps.