Problems with Interruptible Activity Region

Hello
I use Agilian Satndartd Edition v 3.1 Build 20110113 and I have problems with displaying Interruptible Activity Region. After update of its shape IAR disappears from diagram, however it is possible to select it from a tree (Show View) - see attachment.
Second question is, why IAR is not contained (in a tree) within Structured Activity Node?
Best regards
Marcin

IAR.PNG

Hello Marcin,

This seems to be come kind of z-order issue. Would you mind send me your project file to have a look?

Best regards,
Rain