A get / store for all values can take a little time. It can take upwards of a couple of minutes, depending on the noise on the line.
When you say you see no activity in the SDM window for a matter of a minute or two, is it really or minute or two or more like 10 seconds? We have timeouts in place that should cause an error if the time period exceeds approx 15 seconds (can vary a little).
Be aware that we are creating a new version of the utility that will let you download one program at a time, making it much more manageable.