What revision CPU board is it? The 1mb Agnus not working tells me you have a really early revision where there'd be no jumper. Instead, you have to cut a trace on the mobo. I don't know which one off hand, but trying searching the net 'til you find it...
As far as the computer being flaky when you move it - well, that's kind of obvious... you've got a short or bad connection somewhere. Triple check that power supply mod and make sure there are no solder splashes or screws laying near circuitry.
