Hmm. Are you using P5 or P6? I'm more conversant with P5 (I only got P6 recently), and I never came across either of the problems you mentioned...
BTW - I have noticed that in P6 you can't rely on the cloth-rooms preview screen (which you can do in P5). You have to wait for the sim to finish before you can see exactly how it has worked (it's a PITA!)

If the figure moves, the cloth should move with the figure (as long as the character is checked for "collide against", of course. The figure moves the cloth..
NB - When checking for "collide against" for a figure, always use the figure's name, not "body"..
BTW (not sure of my facts here, but..) if the other clothing (shorts in your example) is conforming (and has been conformed), not dynamic, that may also account for the auto-collision..

If any other articles are parented to the figure then they will, by default, be included in the collision tree. You have to uncheck them manually (prefererably at the time you check the figure, the cloth room can take a horrendous time to re-caclutlate collision object after the 1st one).

If you are doing calculations for multiple dynamic cloth, start from the inside and work out (obvious I know, but I've seen that come up a couple of times..). Also, if the original props are being "fitted" to a different/morphed, or are not in a "pre-draped" form (many aren't), do that for each article (in innermost to outermost order) first, saving or creating morphs for each as you go through the sequence.
THEN (and ONLY then), do the posing sims for each (in order). The reason? Supposing you have a long jacket or cardigan or somesuch that needs to be draped over a mini-dress (or whatever) and that the mini-dress starts out as an almost-horizontal circle. It would be almost impossible to prevent the upper clothing from colliding with the undraped mini...

Re: "Is it advisable to restart poser everytime? should you always delete the simulations and start over instead of just recalculating?"
As ever there's no hard-and-fast rules here.
It's probably a memory fragmentation thing.
It seems to depend on the number of polys in the clothing, the extremity of the pose and whether Poser has decided it's not getting out of bed for.
Usually I can get away with 2-4 re-calculations (I always do a "clear simulation" 1st) before coming up with glitches..
(NB - that's "clear simulation" - not the "delete simulation").
I have found it good practice to set up everything ready for the sim then save the scene as a pz3 file. Then I run the sim. If all works, save the result as a new PZ3 file.
If it fails, I quite Poser, (take a tea break to allow myself to utter swear-words in private), re-start Poser, and re-load the PZ3 file (which maintains all the Cloth-room settings etc. Make any corrections for things which might have caused the sim to go wrong, save the file (over the previous one - it didn't work, there's no point in keeping it) and try again..

Be warned: this can seriously affect your hard-drive space. Not only does Poser save the pz3 file, it also saves a file for each piece of clothing, holding the progressive morphs of the cloth.

Best to delete old files on a regular basis..

Hope this helps,

Cheers,
Diolma

PS: A lot of it is the old "suck it and see" technique (AKA "trial and error"). You gradually get a feel for what will and what won't work...but you have to go through it to find out.

PPS: Exit and re-load Poser at least once an hour. Not only will this save your eyesight and lessen backache, it frees up Poser's fragmented memory..

Message edited on: 10/08/2005 15:58