Well I found my own solution to priority based routing using net classes.
Its not perfect, but at least it allows some control for staged routing
without having to dig to hard for all the nets.
The reason for this is to provide the ability to route critical signal first
(and potentially lock them) and then routing other signals in some sort of
order. The way to achieve this is by setting a call for each net that
requires priority based routing.
The execute the ULP which provides board stats, and select all the nets of a
certain class. Copy that list to a text editor and make it all one line of
The select the autorouter icon | select and paste that line of net names
into the command line followed by a ; The semi-colon tells the autorouter
to start routing the selected net set.
Repeat this process for other net classes (priorities) until your board is
routed. You may want to stop and hand optimize some of the routing between
Hope this helps someone, because the autorouter SUCKS at routing fine pitch