I have spent quite a bit of time creating some custom Line and fill patterns but only to find out they are attached to the drawing I created them on, and not accesible from other drawings. How do I move these patterns to the default generic template for all drawings? ???
The default generic template for all drawings is the holy grail of Visio. A lot have searched it and none found it ;).
Use templates instead.
Put custom pattern shapes/masters on a stencil, then open them when you need them. Think of them as a resource.
Or simply open a document that contains custom patterns. ALL open documents will be able to see All custom patterns in ALL open documents. Again, the open-resource philosophy.
Apply them to shapes. Copy shapes into a drawing. Shapes in drawing will then have access to custom properties, as they get copied over. But watch out for file-size bloat due to unused custom patterns.