Bryan, the rule of thumb is simple you want to allow for the work done, energy generated to settle in before you do anything that would upset that process. Ideally a meditation after qigong would be best. The shower would wash away and literally ground the energies that are settling into your physical being.
Food and bathroom have similar distractions and this is obviously applicable to meditation as well. You don’t want your resources focused on digestion when it should be focused on relaxation and integration of new healing energy generated. Bathroom would tend to deplete the energy that needs to settle.
The other things you mention vary only in that you want to allow for a relaxation time if possible. For example jumping from meditation into hurry up running late and speeding down the road to your destination would be contradicting a little,, 
just a little. I think you get the picture; it is more common sense than anything complicated.
[This message has been edited by Ascending1 (edited December 29, 2003).]
[This message has been edited by Ascending1 (edited December 29, 2003).]
