Hmmmm...
Well, first, it is possible to operate a computer even in a flatlined bias. The chance of success is very low, and the computer is likely to error quite a bit, but since Operate Computer is an 11@0 skill when it's entirely user friendly, the computer has a chance of turning on and doing what is asked. Programming, too, is possible, as it is an 11@1 skill. Hacking (bypass security) is not. He can use the computer, but he can't know whether the results he gets are right, and it has a high probability of crashing--shutting down abruptly without damage to itself but without saving data.
Second, there is no P15@10 Do Anything skill; there is a M15@10 Do Anything. It is the equivalent of a wish, really, but serves a secondary function: if a spell does something that does not fit under any other category no matter how broadly defined, this is the place for it.
I'm also not entirely sure that you could raise the bias with such a skill. You could probably create a skill that temporarily raises the mag bias, but since you can only do the skill (even by device) in a world with a curve of 25, the only place it's going to be useful is going to be in 0@25 worlds, where the device itself is going to be less than fully reliable. However, you can't talk in terms of bias when you craft a skill. To the player, bias is a technical term that describes structures within the game. To the character "bias" is a word used to recognize that worlds favor or oppose skills. The character knows that sometimes some skills don't work, and sometimes skills are more difficult, but he can't put bias levels or intensities on anything. "bias level" and "bias intensity" to the character don't mean more than the degree to which things are possible in a given world.
That tells me that any skill would have to be couched in terms that mean either "make the impossible possible" or "increase the chance of success".
On the latter, that's a simple 1@ blessing, and if it works in that world it will sit-mod your chance of success--but it won't change the bias, only your chance of success.
On the latter, well, we've already established that the skill will only work in a world with a 25 bias curve in magic, there is nothing in the mag bias are that won't work. Still, the point was to make it increase the bias in the tech, psi, and bod bias areas--and it won't do this, either, because of PLR. Yeah, you'll see that abbreviation from time to time. It stands for Path of Least Resistance, and it means that wishes will accomplish what is wished by the simplest means possible. The fact is, anything you can do as a tech, psi, or bod skill you can also do as a mag skill--hence the Do Anything listing. So you want to make your explosives work, and you set them despite the fact that you know that for some reason this type of explosive won't work in this world. You use your M15@10 do anything to "make the explosive work", but what you get is a magic explosion in the location of the technological explosive. The fact is, you're bringing supernatural power into the universe to make it do something, and it will do what you want done, but it will be done by supernatural power.
There is no psionic equivalent of a wish because in order to "do anything" in psionics, you have to be specific. You can of course do anything by means of psionics in a world with a curve of 25, but again, you will be accomplishing the results psionically. Bias is not controlled by psionics; it is controlled by two distinct but related factors: 1) the level of knowledge among the indigs somewhere in the universe; 2) the decision of the god or gods that rule that universe. These come to the same thing: if the gods have decreed that the bias is low, then the indigs don't know more than they can know under the bias; if the indigs have learned more than the bias allows, then the gods must have allowed the bias to rise. If you want to change the bias, you must either increase the level of knowledge broadly among the indigs, or get the gods to change the rules. Gods do not change the rules casually or for brief periods of time or location; they change them for long periods of time, usually very gradually. Even terribly chaotic gods maintain that much order in their universes.
Your psionic skill thus is going to work much as the mag skill: your fusion rifle "works" because of a psionic create energy ability. However, since psionics doesn't allow that nondescript equivalent of a wish, you will not be able to create one device that does everything.
You can probably find a way to create a subuniverse. There's actually a technological method of doing so discussed under space travel in the tech chapter. There is probably a psionic way to do it that just is not coming to mind at the moment, and I'm sure it can be done by magic. (I doubt there is a bod way to do this; bod skills tend to be limited to the self or those connected to the self.) So you could in theory create a sub-universe around yourself, and you might be able to establish the biases you want. However, very few skills will cross a sub-universe boundary at less than a -50 sit-mod penalty, so it is questionable how much benefit that would give you.
You're wrong about the symbiont. Your relationship to the symbiont is a bod skill, but its relationship to a mag or psi device would be, for it, a mag or psi skill as appropriate. You can't activate a mag or psi device as a bod skill, because the energy is what defines the nature of the skill, and therefore even if this appears to be done by physical movements (holding, staring into, shaking, twirling) those are support for the skill (ritual or technique), not the performance of the skill itself. You can't bypass the fact that to work magic you have to work magic, and to perform psionics you must perform psionics. Note, too, that psionic devices are limited in what they can do by the bias intensity at level 1. Although you could in theory make your mag device a M1@2 always active device, this would mean 1) that it would not work in any universe with a curve of 2 or less and 2) that in any world whose curve was at least 3 and not at least 25 it would be constantly botching.
I think I covered everything. Did I miss anything?
--M. J. Young