Thank you KBWBE, I will update ASAP.
Any possibilities of an assembly overlap checker being added at a future date?
I am using A2 assembly checker in V18, I just have to ignore the "No module named "objectProxy"" message and the checker works fine.

OS: Windows 10 Word size of OS: 64-bit Word size of FreeCAD: 64-bit Version: 0.18.16110 (Git) Build type: Release Branch: (HEAD detached at upstream/releases/FreeCAD-0-18) Hash: f7dccfaa909e5b9da26bf50c4a22ccca9bb10c40 Python version: 3.6.6 Qt version: 5.6.2 Coin version: 4.0.0a OCC version: 7.3.0 L...

KYKO stirling motor fan.

I thought it prudent to include a detected overlap achieved by displacing the axle by Z-0.1mm just to show A2 WB works with A2+ assembly if required.

Yes, in fact I did have several overlaps which it caught and I rectified, perhaps I should have included the failures also..........

As previously posted, here is a slightly larger assembly file of a tipping wagon although created and assembled with A2+ in V0.18 I ran the Assembly2 WB wich gives an initial error when selected however still seems to do an overlap check successfully as can be seen in attached images. Hope this migh...

Thanks for your comment KBWBE, I thought it was my newness to A2+ that I couldn't find something that is not there. Although probably not the right thing to do, I tried a check using Assembly2 WB from FC V0.16 with a small number of components and although it throws up an error at the start it did s...

OS: Windows 10 Word size of OS: 64-bit Word size of FreeCAD: 64-bit Version: 0.18.16110 (Git) Build type: Release Branch: (HEAD detached at upstream/releases/FreeCAD-0-18) Hash: f7dccfaa909e5b9da26bf50c4a22ccca9bb10c40 Python version: 3.6.6 Qt version: 5.6.2 Coin version: 4.0.0a OCC version: 7.3.0 L...

Thank you 'openBrain' for the information, I have a little better understanding of the Dependency graph now. Thank you 'Willem' for your help, I did note however that the bottom radius is incorrect (should be 72.55mm) and would not mate with the boiler shell. probably caused by the flange fillet cau...

Thanks for your advice 'Willem' I will certainly try your suggestion.
I am finding V0.18 difficult to use, probably an age thing..........(75)
Regards.