Two things:
1) Regarding 'show', make sure you set your labels to .visible := true [I think] this could replace the 'show';
2) There was a comment earlier about debug settings:
[...] Have you set all the debug checks (range, object ... checking)? -CRriot -gt (also try -gtt or -gttt)
Turned optimization to zero -O-
Added Heaptrc -gh (additionally search the forum for "keepreleased" option of Heaptrc)
I think you have these settings ON, but just in case: select Project > Project Options > Compiler Options > Debugging > Checks and Assertion. Set all the options (I/O, Range, Overflow, Stack, Verify methods calls & include assertion code). Also make sure "Generatie info for the debugger..." is ticked. Finally (in the bottom section) do a run with "Use Heaptrc..." ON.
cheers
S.