Documentation is shortcoming of U++. Not everything is documented so far.
With ProgressIndicator, there are two values
- "total" is the total number of steps required to perform the operation.
- "actual" indicates actual progress, actual number of steps performed so far.
"total" can be 0, in that case ProgressIndicator displays just "running" bar, used when total number of steps is unknown.
Yes, more widgets can be added to the menu - see reference/UscCtrl.