I think that you may need to first add the instance to the model (or some other) entities collection, then apply a transform, set name, etc…
There are quite a few situations with the C API that a coder must do things in a certain order.
For an example of incorrect order and correct order, see topic …
Also there is an important note about using API v6.0+ (2018 and newer) with regard to releasing SUComponentInstance references. See …