Hi Ruchir,
I tried your scenario and found that this is how MII behaves.
If there are 2 messages with same name and same message type and with processing type as category and other one as transaction, then the one with 'Category' processing type will always get processed and not the transaction one.
You will find that if you delete the message with type 'category', then the one with 'transaction' will start getting executed.
Another point to consider is that this is only because you have SAME 'message name' AND 'message type' for both your processing rules.
Instead, if you had a different 'message type' OR the 'message name', then they will both be considered unique and then whatever is the processing rule created, will get applied.
I am also curious to find out that how did you manage to save a processing rule with same message name and same message type? When I tried it, the system did not let me save it.
Regards,
Rutika