exact instructions?
 

I rarely feel the need to use it, so I found myself not doing it right.
I want to set up some of my atgm to fire only at MBTs, no matter what direction they come from (imagine a scenario where the enemy has surrounded you or whatever.

I end up having an atgm unit not firing at anything automatically.

I won't bother you with what I do because obviously I do something wrong, can someone please give me detail instructions of how to do it?

Re: exact instructions?
 

Assuming you have the CD version (with full Op Fire filtering):

1) Hit "Y" to bring up the Op Fire menu
2) Hit the "Filter" button
3) Set "Steel Armor Front MAX" to 255
4) Set "Steel Armor Front MIN" to 1 (I often set to 10 so ATGMs aren't wasted on APCs)
5) Set "Armor Engagement Range" to whatever the range (in hexes) of your ATGM is
6) Set other setting as desired
7) Hit one of the three Blue disc buttons to save these settings
8) Use the "N" and "P" keys to cycle to your ATGM
9) Hit the matching Red disc button (if you saved in Blue #1 hit Red #1)
10) Hit the "Apply" button
11) Hit the "Exit" button

Walla !

Re: exact instructions?
 

To go straight to filter screen can just hit O button rather than Y
Depending on opponent set to 25 in stage 4) or there abouts if only want to hit MBTs
Remember you need to do stage 9) each time you select a new unit or group.
While at it for ATGM units I set infantry & soft vehicle engagement ranges to 3