[Lazarus] savedialog issue

[Andrea Mauri]

Dear all,
I encountered a strange behaviour of TSaveDialog.
I have a big project, inside of it many TSaveDialogs.
Recently I found that sometimes the dialogs are not shown.
I didn't find any explanation on this behaviour, here what I understood:
TSaveDialog is shown on execute all the times except when I got 
exceptions (out of memory exceptions that are managed using try finally 
or try except).
I tried to go inside the execute, since when I call execute it gives me 
back False without showing the dialog.
In
function TCommonDialog.DoExecute : boolean;
FUserChoice is assigned 2 (mrCancel).

I don't know why. I would like to know where/what I have to check in 
order to understand this behaviour.
Anyone can help? Any suggestion?

I use:
Lazarus 0.9.31 r37846M FPC 2.6.0 i386-win32-win32/win64

Best regards,
Andrea Mauri