I just released the first draft of my package PackageDisplay to  SqueakSource.
It is like SystemProgressMorph et. al. but with a lot of bells and
whistles added.
It is not a suitable replacement for SystemProgressMorph though because it is
too large and specific for that. SystemProgressMorph could be made a subclass
of one of its classes though.

It is designed largely to meet my specific needs but since it's MIT
anyone may use it,
steal components, or move components of it to Squeak.
It has a utility class category with useful classes for things like
array permutation generation and array multiset permutation
generation, numeric partitioning of a number, and a class RangeList
(which I will be expanding upon later).  All of these classes will be
removed when the package meant to contain them is ready (not soon).
There are also a number of utility methods that could be stolen or put
into Squeak
proper.

It probably has lots of bugs, so bug reports appreciated.  Comments on
its function,
design, and implementation most welcome.
Proposals for improvements or extensions will be considered but no promises.
If you need access to make changes let me know.
If Levente Uzonyi likes it but feels compelled to rewrite it
completely from scratch, thats OK too. :-)

One of my reasons for releasing it is because of a bug I could not fix.
It is supposed to be possible to turn on the ability to catch user interrupts
but when this feature is turned on and an interrupt generated while
the progress bar
is displayed the interrupt is caught but not processed until the
progress bar closes. :-(
Of course the interrupt was meant to be processed immediately.
If anyone can tell me how to fix this bug (or better still send me the
code or add the
code to the package) that would be great!

If you use the package I would appreciate knowing since I would like to know
who may be impacted by changes I make in the future.  The more software
impacted the more careful I need to be.

Regards,

Ralph Boland