the masquerade settings field that gets added to the user profile form does not have any weight assigned to it.
as soon as a user adds additional fields; since the masquerade field does not show on the manage fields form, it can't be moved relative to the new fields and ends up showing up in the middle of these new fields:
attached patch simply assigns that field a weight of 10 to move it down with the other admin fields
FAILED: [[SimpleTest]]: [MySQL] Invalid PHP syntax in sites/default/modules/masquerade/masquerade.module.
FAILED: [[SimpleTest]]: [MySQL] 16 pass(es), 2 fail(s), and 0 exception(s).
FAILED: [[SimpleTest]]: [MySQL] Unable to apply patch masquerade-add_weight.patch. Unable to apply patch. See the log in the details link for more information.