Attributes acting weird

[Stefan Videnov]

Hi everyone,

INFO:

In Teamwork we have a complex Main Model file where 5 different models are united. Since we transfered from archicad 27 to 28 we observe a mishap of the Surfaces in our Windows. We decided to continue working with the old 27 libraries. We are not using an Attributes file, because of the added complexity. We are following a strict naming convention and we didn't have many problems prior to moving the project to 29. The involved surfaces have been set since the beginning of the project and we started encountering the problems only recently. Nothing has been reindexed or renamed. We always reserve-all and sync attributes when updating hotlinks. Because of the complexity we decided to sync attributes by name and not pay attention to the indexes. 

I believe what we are experiencing is a bug, but I might be missing something

THE PROBLEM:

In our Source file the window uses a surface named _L2.1 gevel kozijn for all windows components: Frame, Turning part en Surface Sill
Screenshots Source model surfaces:

However in our Main Model the surface suddenly is switched to _Surrounding green buffer, but only the Frame and the rotating part . The Surface of the Sill has remained the same _L2.1 gevel kozijn

Screenshots Host model ( Main Model) surfaces :

You can see that the window has the grass surface^

The issue comes from the attribute indexes. 

Index of the  _L2.1 gevel kozijn surface is 657 in the source:

In the target file _surrounding green buffer has the same index.

Obviously, In MainModel Archicad has started pulling the index of the Surface instead of the Name, but I do not think that is normal behavior.
It doesn't explain why the Surface of the SILL has remained the same.

Can anyone explain this behavior?

I fixed the issue with these mismatching windows by reindexing all the involved attributes in both files, but yesterday we got the same mismatch in another building. 

Thank you!