Can't get observer() to work…

This is the 2015-09-25 daily.

I have Python code like:

            leftRegion = <some region>

            changeEvent = leftRegion.onChange()
            if not leftRegion.observe(True):
                print "Could not start observer"
                exit()

The program always exits (i.e., the observation can't start), with debug/error messages like:

[debug] Region: R[544,943 790x83]@S(0): observer CHANGE : 1443785667124 with: 50
[debug] Region: observe: starting in R[544,943 790x83]@S(0) for 1.0 seconds
[debug] Observer: resetting observe states for R[544,943 790x83]@S(0)
[debug] Observing: add observer: now running 1 observer(s)

[debug] Observer: update result: Patterns: false
[debug] Observer: update result: Changes: true

[debug] Observer: update result: Patterns: false
[debug] Observer: update result: Changes: true

[debug] Observer: update result: Patterns: false

[debug] Observer: update result: Changes: true

[debug] Observer: update result: Patterns: false
[debug] Observer: update result: Changes: true

[debug] Region: observe: stopped due to timeout in R[544,943 790x83]@S(0) for 1.0 seconds
Could not start observer
[debug] Sikulix: cleanUp: 0
[info] Exit code: 0
[debug] Exit code: 0
[debug] Sikulix: cleanUp: 0

So the observer can't start… or it does start, but only runs for 1 second? (and what's the "Changes: true" bit? There's nothing changing on the screen at this point.)

If I try: leftRegion.observe(FOREVER, True), it tells me the observe functions expects 0-1 arguments, not 2.

If I try leftRegion.observe(background=True) (with or without a time arg), it tells me observe doesn't take any keyword arguments:

[error] script [ DOFFOptions ] stopped with error in line 235
[error] TypeError ( observe(): takes no keyword arguments )
[error] --- Traceback --- error source first line: module ( function ) statement 60: AssignmentTasks ( collectComplete ) if not leftRegion.observe(FOREVER, background=True):
[error] --- Traceback --- end --------------
[debug] Sikulix: cleanUp: 0

Any ideas?

(Oh, and it slows down my mouse too. ;-) )