The ability to attach files automatically to a communication template isn't something I've used very often so I've never had to try and do this exact scenario. Something that might work is on the attachments in SR, try and set the COPYLINKTOWO attribute to 1. When this is set on the attachment and the "Copy Doclinks to Work Order on Save" is enabled in the System Settings dialog in the Organization application, attachments that are associated to supporting records (such as Asset, Location, or in this case SR) where that flag is set should get created as a document directly against the WO. That should enable the out of the box functionality to work.
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Steven Shull
IBM
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