tim Rowledge uploaded a new version of SUnitGUI to project The Trunk:
http://source.squeak.org/trunk/SUnitGUI-tpr.69.mcz

==================== Summary ====================

Name: SUnitGUI-tpr.69
Author: tpr
Time: 19 November 2017, 3:37:59.182697 pm
UUID: d152c829-9818-4d11-ac05-d325d65a4c80
Ancestors: SUnitGUI-tpr.68

Drop the use of the abominable instVarAt*

=============== Diff against SUnitGUI-tpr.68 ===============

Item was changed:
  ----- Method: TestRunner>>runErrors (in category 'actions') -----
  runErrors
+ 	self result resetErrors.
- 	self result instVarNamed: 'errors' put: OrderedCollection new.
  	self runSuite: self suiteErrors.!

Item was changed:
  ----- Method: TestRunner>>runFailures (in category 'actions') -----
  runFailures
+ 	self result resetFailures.
- 	self result instVarNamed: 'failures' put: Set new.
  	self runSuite: self suiteFailures.!