Conflict between augmentations?

and there is no way to do it?
some research...cryo pod...something....

those are the only ones that really changes playstyle a bit

tha bad thing is that those augmentations can't be added to head,arms and legs

Yep, you can only have one 'special' augment and one ammo augment on a gun. So you can have say, shield oscillator and seeking plasma, but not shield oscillator and bio-converter.

BTW, of those three augments you listed only the shield oscillator is really worthwhile. For the other slots just use either combo damage augments (if you're using a build that can regularly do combos) or kinetic coils (to boost weapon damage).

Edit: or an augment that grants you extra mod slots, if you want them.

I wanted to know if there are any issues with augmentations stacking. So I created an HyperGuardian X Chest with

Battlefield assist module (When health is 20% or lower: +25% Resistance to All Damage)
Kinetic Coil (+5 Damage resistance)
Kinetic Coil (+5 Damage resistance)
Kinetic Coil (+5 Damage resistance)
Kinetic Coil (+5 Damage resistance)

So I take that to mean that I have +20% Damage resistance all the time and when my health <=20% i get an addition 25% of damage resistance for a total of 45% resistance to damage. Is that correct?