So testing the spindle with NO POWER you should get continuity between #6 - # 2 and #5 - #1. with NO continuity between #6 - #4 and #5 -#3.
Then with power applied you should get continuity between #6 - #4 and #5 -#3 with NO continuity between #6 - #2 and #5 - #1.

If you get anything else then you have a faulty relay.

Also, you don't need to use the second set of NC contacts for the ATC release, you can just use the NC of the first set of contacts because it will change over when the relay turns on. HOWEVER, if you are using this to actually release the tool rather than just forming an inhibit to the solonoid it's a very bad idea because every time the spindle stops it will drop the tool.?? . . . Surely this is not what you meant.!