GI / GR Cancellation - PCS Message Category - MES to SAP

Hi All

In Our scenario we are receiving input from MES system to SAP.In Middle ware we are mapping the input received from MES system. From MES ,  inputs are received via Idoc WMMBXY. same will be mapped in Message Category .

Now Requirement is Goods issue & Goods Receipt cancellation should be done based on input from MES to SAP.

I have found that there is no standard process message Category  available for Goods issue & Goods Receipt cancellation.

Q1 :Do we need to create New Message Category for this requirement or is there any alternate available..?

Q2: If it has to be  created newly , found that there is standard FM called COCI_CANCEL_MATERIAL_MOVEMENT to assign as Destination inside Process message Category (To cancel the GI/GR using MIGO) Is it correct one ?

Please share your experience on handling the requirement

Q3: We have Standard message category for Goods issue & Goods receipt , Can we try to use this by changing the Movement type alone . For this need to copy the GI/GR sd message category and use this with movement type condition 262 /102 .Is it advisable?

Thanks

Sachin