First, thanks for a great product!
I was planning to use a number of button/dialog pairs to work kind of like a tab view, with each button first closing any open dialogs and then opening its own dialog (tab). However, the non-modal dialogs block access to the buttons, thereby preventing this to work. Is this by design or is it a bug? I would have expected only modal dialogs to block everything outside the dialog.
Sorry for the late reply.
Yes it's by design. Buttons are disabled under an opened dialog (modal or not).
To force enable a button that's under a dialog, just set the "ignore input" option of the button to NO.
A modal dialog means that when it's opened no other dialog can be opened.