Magic/psionics nontransparency only means that things that specifically refer to spells only affect spells, not powers, and things that specifically refer to powers only affect powers. It doesn't mean that spell effects and power effects can't interact, just that effects that are specifically written to interact with one type of magic system only interact with that system and not all others.
Mind blank, for example, would prevent mind-affect powers because it provides protection against mind-affecting spells and
effects, not just spells. It protects against any mind-affecting effect, regardless of whether it's a spell, power, non-magical extraordinary ability, or kooky homebrew ability. Likewise,
resist energy and
provide resistance/immunity to a type of energy damage, and don't care at all what the source of the damage is. They'll protect equally well against the fire damage from a
fire shield spell, a fire elemental's attack, a lit torch, a fire
energy missile power, etc.
On the flip side,
dispel magic specifically deals with spells and magic items, so it would have no effect upon powers or psionic items in the same way that it has no effect on supernatural or extraordinary abilities. Similarly,
detect magic specifically detects magical auras, so it won't pick up psionic auras.
