There are growing signs that the nomination of Kenneth Adelman as director of the Arms Control and Disarmament Agency may be headed for more trouble. Senate foes of Mr. Adelman are preparing a list of questions for him that could further delay a confirmation vote. A key member of the Senate Armed Services Committee called on President Reagan to withdraw the nomination. And a source within the administration accused Mr. Adelman of having lied. But Reagan said Friday he was standing by his choice.