Having issues with Global Damage Modifier applying crit damage. D&D 5E by Roll20 sheet

So, I've got a rogue build with the Mage Initiate feat and went with Warlock.  I have three Global Damage Modifiers setup.  One for Sneak Attack, one for Green Flame Blade, and one for Hex which look as follows: 0?{Sneak Attack|No, |Yes,3d6} 0?{GFB|No, |Yes,1d8} 0?{Hex|No, |Yes,1d6} The trouble is, when I crit, only the Sneak Attack applies the extra damage.  I have tried placing all three in a single Global Damage Modifier, but that doesn't seem to work either. Any ideas as to how I can get the extra crit damage to apply to all three? Thanks in advance.

The global damage modifiers cannot handle queries when calculating critical damage. My recommendation is to separate the three instances of damage (sneak attack, green-flame blade, and hex) into different global damage modifiers and then check/uncheck the damage modifier when necessary. This would remove the need for queries.

I have each in a different global damage modifier.  Unfortunately, with the build, all three modifiers will be getting utilized most times.  Rogue always using Green Flame Blade, rather than standard attack, adding the Sneak Damage (hopefully in all situations where that is relevant), and having Hex up when able.  Lol  What I think I'm going to have to do is just do Sneak Attack under the Global Damage Modifier, and then have GFB and Hex setup as just attacks, without attack rolls, and use Result 1 and 2 for their results.

Is it possible with global damage modifiers to modify the crit value? We use max die on the initial damage die and roll the critical die.

Not currently no. The only way to change the crit value is through an individual attack in the section.