With build 15.4.1003, new improvements were added to allow for better tool priorities control, with a focus on improving Multi-Pass Tool priorities (aka 900 Tools).  Below is an updated list of Route Tool Priorities, including new Multi-Pass Tool specific priority settings.

Priorities are broken up into two primary areas, Route Operational Priorities and Route Tool Priorities.

1. First (Highest) Priority: User-Defined Priorities. These priorities are determined by onscreen selections using the "2D Machining Tools > Nest Tools" option to "Assign Priorities to Routes."  This function is used for the composite.dwg (nest) or the parts.dwg (single part).  This would be used in conjunction with either "Update Existing GCode File From Drawing" or "Make New GCode File From Drawing" to create GCode.
   
2. Second Priority: Machine Token Priority. Routing machine tokens have a "Sequence" or "Priority" parameter.  This machine token parameter value will be recognized as the second-highest level of routing priority.
   
3. Third Priority: Toolfile Tool Priority. Within the Toolfile, each Router Tool has a "Tool Priority Number."  This option is enabled by selecting "Allow Tool Priority Setting" in the Settings Tab of the Toolfile.  When this option is enabled, you are required to assign a priority to all tools. Otherwise, it will not function.
   
4. Fourth (Lowest) Priority: Minimizing Tool Changes. Minimizing tool changes are being used throughout the route optimization process without having to adjust settings.  Ultimately though, each of the superior priorities can and will trump the minimization of tool changes if it is required by the operation and priorities set.
   

Route Tool Priorities affect specific tool priorities and will work in conjunction with the Route Operational Priorities. By default, 900 Tools (Multi-Pass, Step, and Incremental Step) are prioritized over non-900 route tools. All tools are affected by their assigned Route Operational Priority, as seen above.

• Reduce Tool Changes: Tools used within a Multi-Pass Tool (900 Tool) will be optimized with other operations to reduce tool changes.
  
• Group Tool Operations: Tools with the same Common Tool Name (i.e., 900, 901, 902, etc.) will be kept together.  For example, if we have tool 901 used in on two routes and tool 902 used on two routes, this will group both route operations using 901 together and then both route operations using 902 together.
  
• Segregate Tool Operations: Each route operation using a Multi-Pass Tool (900 Tool) with this setting will be run in sequence from top to bottom (depth) of the route, then proceed on to the next operation.  This may increase tool changes significantly.