I've never tried any hand pasting of my own before, or reflowed in a toaster oven or skillet but I work in an assembly house where we regularly reflow, TQFP's, QFN's, and BGA's. Here's a few things to keep in mind when doing these fine pitch parts.
1) Your paste needs to be DEAD ON. You said that there is already some bridging with the paste before reflow and this will not work well at all. Take your time with pasting and be especially careful that you don't smear the paste when lifting off the stencil.
2) Most lead-free pastes do not flow at all. This means it will not pull your part onto the pad, wherever it is, that's where it's staying. So your part placement needs to be DEAD ON as well. More expensive pastes containing silver and other elements will flow much better. But in general lead free is much more difficult to work with than leaded. I would consider switching if tolerable/possible.
3) I don't know what your reflow setup is, but temperature profile is important in reflow. Try to have a smooth, gradual warm up period to let the fluxes mix well with the solder. Also, check you "time above reflow" this is the amount of time the board spends above the reflow or melting temperature of the paste. It may be that this is not long enough to allow the paste to become molten and have time for the surface tension to pull your part into place
I hope this is at least somewhat accurate information...
Let us know what you find out!