I have never used anything but an exposure unit and sunlight to expose films. but here's my 2 cents.
when you coat your screens with emulsion make sure you get good clean coverage.
when you burn your screen try using a piece of glass to hold your film tightly against the screen.
before you burn your image, take a coated screen a perform a
step test to determine the proper exposure time.
when you wash your screen out, give the water a chance to work on the emulsion, don't try to FORCE it out, damaging other areas of the screen.
when you print with water based ink(or ink that will dry in the screen), keep the stencil flooded (ink in the screen where the image is)so the ink doesn't dry as fast and you'll get a little more working time.
take your time and understand everything thats happening during the process....
good luck.