I run both KM and Quicksilver (please let's not start a debate about that). I tried to add a very simple macro which inserts Date & Time and when it is invoked the first part of the date is inserted and then the QS interface comes up and the rest of the date is lost. It does not seem to matter what I use to trigger the macro. I have tried to disable the macro and use the same trigger and it does not invoke QS If I quit QS the macro runs fine.
Post your macro so we can see what's going on. Also, what is your QS hotkey?
Inserted how? Never used Quicksilver but there's the possibility that if you are using KM's "Insert text by typing" then QS might interpret those as a trigger -- try using "Insert text by pasting" and see if the problem goes away.
You can then decide whether to stick to pasting in the text or to disable/change the trigger of the QS function you're activating.
The macro does Insert by Typing but QS triggers all begin with Option, Cmd, or control. none of which are in the Date string (to my knowledge).
This is Peter's macro – not yours.
Are you asserting that this macro has the problem you describe with Quicksilver?
Try changing to insert-text-by-pasting instead of by typing.