[galex]

Where change the UTOOL number for Fanuc?

[RoboDK]

You can use the Fanuc post processor called:
Fanuc_R30iA
(right click a program, select "Select Post Processor").

With this post processor, if you use numbered tools and reference frames it should use the appropriate UTOOL and UFRAME respectively. For example, naming your tool "Tool 3" should generate UTOOL 3. Or naming your reference frame "Frame 4" should use UFRAME 4.