Hi,
I am trying to make a simple equivalent to the maya “point constraint” as a simple OTL. it just contains two nulls, one being a the world origin, and one to be contrained to the object path provided in a parameter. The translation parameters of the second will be overriden by an object CHOP computing the position between the world origin null and the object whose path is provided.

When I am creating it, it works fine, but the problem is that when I call a new one, it doesn't work apparently because the CHOP doesn't export anymore, even if the export flag is on. it seems that I need to “allow editing of contents”, and toggle twice the export flag of my chop…is this step really necessary, or I am making somthing wrong? As it is not the first time this is happening to me, I may have not understood something…
the solution I found is to have a callback script ( called when a parameter of the OTL changes ) like this:

otunsync `oppwf()`; #allow editing of contents
opset -o 0 `oppwf()`/chop/export; #turn off the exportflag
opset -o 1 `oppwf()`/chop/export; #turn on the exportflag
otsync `oppwf()`; #does not allow editing of contents

I do not really like that, so I guess there may be a better way to go…
And here is a file containing my “point contraint” operator type.
http://perso.chello.fr/users/f/frading/point_contraint.hipnc [perso.chello.fr]
there is just also a few bones, only here to have objects to test my operator onto.
and please…I really need help about this loosing so much time with these kind of details is really painful! <_<

This has to be a bug. I will submit it.

I also see a problem in your OTL that, due to the bug, just doesn't work either so don't do this but works in a typical object/sop scenario where you want to reference an object in a sop, say Object Merge. You can't change physical strings inside a custom object. You are doing just that with your script when you set the reference to the object in the Object CHOP.

In the first object reference in the object CHOP, put:

`chs(“../../targetobject”)`

You will get an error whenever you apply your changes in the Type Properties dialog that the reference is unresolvable. Ignore this warning.

For now, your clever script with the direct object reference in the CHOP as it works.