I'm having trouble with creating fields and rigid bodies. Sometimes it works, but other times when I go to the field I wish to create or select "create active/passive rigid body", I don't get anything at all. The little text line at the lower left just says, for example, Turbulence: create turbulence...etc... while my mouse is on it in the pull-down menu, but then it disappears when I click on it and nothing happens. No field, no rigid body, nothing. This only seems to happen on some of my files, I've gotten it to work before, but can't figure out why some perfectly files just won't accept any fields or rigid bodies in them.

I tried copy-pasting a couple of fields from a successful file into an un successful one, but to no avail. I can't seem to link the fields to the objects in the file they've been brought into. Are there any tricks for copy-pasting/exporting to other files? Better yet, how do I coax my Maya into being less moody and letting me use all of its tools in all files?

P.S. I'm using Maya 7.0 for mac

Thanks!