As there seem to be very frequent repetitive questions, why not use the Text box in the home screen |^| of UD agent, to add a second paragraph with red text like:

In the 'I' screen a more detailed progress bar can be seen, which may oscillate up and down, as multiple attempts are made to on the same section of this work unit.

or:

The % progress may appear frozen for longer periods, as the WU is split in fixed sections. Progress should still be visible in the 'I' screen

the text may change as different special events are known for varying batches.