from the looks of things your tree must remain indoors, But can receive good lighting outside with no direct light or your leaves will burn, with a top soil with extremely well drainage. If the pot you have it in was bought with the tree at Walmart or at any other store I would recommend finding one specifically for good drainage and re pot immediately !! this tree requires very good drainage, and a good amount of sun. what I have learned form Bonsai Research is that once you have a tree in one spot it is not recommended moving it to much. it must remain there, so if you've moved it to a spot where it gets light; this spot must and should be your trees new place.. Also from the looks of your pictures I think that the soil is not draining well and you could be doing things as directed but harming it at the same time. Drainage is VITAL in Bonsai .. to much water causes root rot and will kill your tree. I would let the soil dry, and do an emergency repot to a pot with good drainage and a top soil with good minerals and excellent drainage. IF you are going to repot as an emergency have your tools ready to do this as fast as possible, new pot with good drainage good soil - that provides good drainage and a root stimulator to help with shock do this fast !! Do the research !! I've attached a link for you !! http://www.bonsai-made-easy.com/ficus-bonsai-tree.html

Wait - it'll either do it all by itself (but take weeks/months) which is most likely, or it won't do it. It's genetic and while it's one thing to try and encourage one to grow in a particular place, or graft one on, you're talking about a whole tree and either of those choices will not really look so hot if done in more than one place. Can you get another tree? You might try cutting yours down - that often will encourage new growth, but whether you get branches or just more leaves is hard to say. I'd do it because of 'nothing to lose' at this point.

Thanks moochinka! I have bad news though! I noticed a whole bunch of ants around where I was keeping the ficus, upon closer inspection I noticed them going below the soil. I loosened the tree from the pot and couldn't believe what I saw. AN INFESTATION of ants. HUNDREDS! So I quickly removed all the soil and had the tree bare root. I contemplated, just repot, or attempt to start a root over rock, which had been my ultimate goal. Stupidly (I guess) I decided to put it on a rock and plant it in a slightly larger pot. Within days that infamous ficus leaf drop began! The plant isn't looking too happy or healthy now. Not sure if this is to be expected with the RoR transformation, if maybe December (which I know isn't the ideal time) to repot and attempt RoR, or if even maybe just a coincidence from the infestation. Do you think I'm going to lose the ficus? Any suggestions to help it spring back? I'm not too ficus knowledgeable other than every one I've ever attempted years ago seemed to just drop leaves (which I had given up before trying to rehab them) Thanks everyone!

Lack of light is causing it to shed leaves. That means it is not using up the water in the soil and it remains too wet too long. That in turn can lead to root rot and eventual death of the plant. The soil also looks like it is not a proper bonsai soil and it is retaining too much water. Bonsai soil or any container soil should be more porous and thus airy. The roots die if waterlogged for too long. Move it to a spot where it is the brightest. Next to a south facing window is best. Contrary to what the label says the more light you can give the better off the plant will be. Direct sunlight will be best. Once it recovers start fertilizing weakly. If you want to gain an understanding of container growing, soil types, watering habitsread this. It is a long post but will start you off in the right path.