I am trying to create 3 bridge piers as family instance by using node RevitUtils.CreateFamilyInstance. But I have a problem and I can’t seem to figure out what’s wrong. As you can see in red circles, every input (feature line and stations) is correctly defined. But the last node creates only 1 pier (other 2 are “null”) and I have lacing set to “Cross Product”. Any ideas?
Last node is yellow because I have geometry scaling set to “Medium” (same problem with “Large” so this shouldn’t be the problem).
I am not exactly sure what you mean by a single item. If you check the most western red circle, there is only 1 item in the list. Is there any other way to operate with feature lines? I’ve checked other users. They are using the same nodes, the same way. Even If I don’t use List.Flatten node, it’s the same result.
Yes, everything seems to be OK if I use only 1 station input.
Try a codeblock with list[0] or the FirstItem node after your List.Flatten node. List structure can be very important in how a node functions. Right now your featureline input is only one item but it’s still in a list. The codeblock or the node I mentioned will return just the item in the list instead of the list itself. I’m not familiar with this node so I don’t know how the inputs are supposed to be structured, but it may help.
Notice the difference between a singleton and a list with only 1 item.
Thank you for that advice. You learn something new every day. Unfortunately the problem still remains. Is it possible to not get stations in a list the same way? I am running out of ideas.
Afraid I’m not familiar with C3D so I can’t say. Is your warning still due to geometry scaling?
Last thing I can suggest is switching lacing back to Auto and changing the List Levels to @L1 for the station input.
Yes. If I change it to “Large” though, it just says that “the operation failed” and still makes only 1 pier and not 3. I also tried using List Levels @L1 on Auto and Cross Product. Problem still remains for “Medium” and “Large” geometry scalling.
Positive. It takes first and last BaselineRegion stations, then divides the region on X parts (based on your input for No. of piers). It is the same if I use node that takes parameters (stations) from drawn Sample lines in Civil 3D.
Is it possible to not get stations in a list the same way? I am running out of ideas. 
