Fragments that are part of combined fragments's operands are not nested when they should be

[jbuusao]

All fragments are generated flat, under the ownedMember of the interaction, even though some of the fragments may be contained by a combined fragment's operand. Three solutions (at least) are possible:
a) Have fragments part of combined fragments under the operand element
b) Have additional linking attributes linking operands to contained fragments (multi-value)
c) Have additional linking attributes linking fragment to container (single-value)

I see that the XMI specification is silent on this implementation, and suggest a) as this is is more intuitive and does not require any additional attribute. Attached: screenshots of a test model and resulting (cleanup) XMI.

Thanks for a great extension, and for considering this issue!