Unable to "Export Selected" as Rhino v5

I need to save part of a model to v5 as Archicad can’t open v6 models. When I save the file I get told that some features can’t be saved as v5, but do I want to proceed anyway? I’m given a choice between V5 & V6, but either way the message at the bottom left corner says it has ben saved as v6 (and Archicad can’t open it). Seems to be happening with two (similar) models.

See the attached screen recording, which I hope is clearer than this message!
Hope you can help.

Rhino 6 SR18 2019-9-23 (Public Build, 6.18.19266.13352, Git hash:master @ 3d84f88dec99b2f4e8b7497e739ed2adc2ba8ef6)
License type: Evaluation, build 2019-09-23
License details: Cloud Zoo. In use by: Kenny McNally ()
Expires on: 4317139-04-29

Apple Intel 64-bit macOS Version 10.14.6 (Build 18G95) (Physical RAM: 32Gb)
Mac Model Identifier: MacPro6,1
Machine name: Kenny’s Mac Pro
Language: en-GB (MacOS default)

AMD Radeon HD - FirePro D300 OpenGL Engine (OpenGL ver:4.1 ATI-2.11.20)

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On

Anti-alias mode: 4x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: Height

Vendor Name: ATI Technologies Inc.
Render version: 4.1
Shading Language: 4.10
Maximum Texture size: 16384 x 16384
Z-Buffer depth: 24 bits
Maximum Viewport size: 16384 x 16384
Total Video Memory: 2 GB
Graphics: AMD FirePro D300
Displays: PL2481H (94dpi 1x)

Graphics processors
AMD FirePro D300 (2 GB)
AMD FirePro D300 (2 GB)
Luna Zero (1920 x 1080 @ 60 Hz)
PL2481H (1920 x 1080 @ 60 Hz)

USB devices
Apple Inc.: Bluetooth USB Host Controller

Bluetooth devices
Broadcom: Magic Keyboard
Broadcom: Magic Mouse 2
Broadcom: Broadcom Bluetooth Wireless Mouse SDP Server, Broadcom Bluetooth Wireless Mouse, Broadcom Bluetooth Wireless Mouse PnP Server

Third party kernel extensions
com.karios.driver.DuetDisplay (1) 66BC2B5B-9F40-3153-B601-518C103CE27E
com.astro-hq.driver.LunaDisplay (1.0.1) DA36D61E-DF34-3D59-84D2-781A01054D2D

Third party plugins

Rhino plugins
/Applications/Rhinoceros.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoCycles.rhp “RhinoCycles” 6.18.19266.13352
/Applications/Rhinoceros.app/Contents/PlugIns/NamedSnapshots.rhp “Snapshots” 6.18.19266.1002
/Applications/Rhinoceros.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/GrasshopperPlugin.rhp “Grasshopper” 6.18.19266.13352
/Applications/Rhinoceros.app/Contents/PlugIns/PanelingTools.rhp “PanelingTools” 6.18.19266.1002
/Applications/Rhinoceros.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/Export_OBJ.rhp “export_OBJ” 6.18.19266.13352
/Applications/Rhinoceros.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/Commands.rhp “Commands” 6.18.19266.13352
/Applications/Rhinoceros.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RDK_EtoUI.rhp “RDK_EtoUI” 6.18.19266.13352
/Applications/Rhinoceros.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/Export_DAE.rhp “Export_DAE” 6.18.19266.13352
/Applications/Rhinoceros.app/Contents/PlugIns/Displacement.rhp “Displacement” 6.18.19266.1002
/Applications/Rhinoceros.app/Contents/Frameworks/RhCore.framework/Resources/ManagedPlugIns/RhinoDLR_Python.rhp “IronPython” 6.18.19266.13352
/Applications/Rhinoceros.app/Contents/PlugIns/export_SKP.rhp “SketchUp Export” 6.18.19266.1002
/Applications/Rhinoceros.app/Contents/PlugIns/RhinoRender.rhp “Rhino Render” 6.18.19266.1002
/Applications/Rhinoceros.app/Contents/Frameworks/RhMaterialEditor.framework “Renderer Development Kit” 6.18.19266.1002

I just tried it with my own file and it works fine.
There must be something special about the object you selected for export.
Please post the file.

Thanks for looking into this John, appreciated.

After my original post I went back into it and this time it saved as v5 (as shown by the text in bottom left corner) which opened fine in Archicad, so I’ve no idea why this is sometimes working and sometimes not. Not sure it will help much but I’ve attached the file anyway. The part I was trying to export was the ‘ribbon’ to the underside of the escalator.

Thanks again.
Escalator Central 0405.3dm (7.5 MB)

When I was having to do this back-saving on a regular basis I’d get the warning all the time but never saw anything actually missing. It could be warning about data from plugins that you in fact have in V5 as well as V6 but it has no way of knowing that…for all I know it’s a boilerplate warning that comes up all the time just to CYA.