couple things that will hopefully help. with the tablet, it seems to be a bug. if there are multiple tablets in a world, when you put something in that it wont accept, it will spit it out either at another tablet, or somewhere random in the entire world. with the machines, there can be a few problems. 1st off where is it located? if its the solar panel is it exposed to sunlight(top) and if using copper make sure its not to long, because you loose 1 eu per 5 blocks with those. but if they produce no energy with batter, perhaps its meant to not be strong enough to directly charge something. if you think any of these fixes could be the why, and it still doesn't work, post again with info on what i talking about.