[Newbies] saving projects: bad blocks?

[Andrew Dabrowski]

I'm working in 3.8, I've put together a simple morph project with a data 
class and a gui assembled interactively using mostly TextMorphs and a 
ScriptableButton.  When I try to save it as a project I get the 
following warning.

'Some block(s) which reference instance variables
are included in this segment. These may fail when
the segment is loaded if the class has been reshaped.
What would you like to do?'

If I decide to go ahead a save it anyway, the resulting .pr file does 
work correctly when I try to load it.  It looks right at first, but the 
button does not do everything it's scripted to do.  I'm guessing there 
is a problem related to the warning above, although the Transcript does 
not show any error messages.

If, after seeing the warning during the project save, I select "and and 
take a look", I get a window labeled "Error: Here are the bad blocks", 
but I don't have clue how to use the information there to fix the problem.

Any help will be much appreciated.