This is the info I got from GRAPHISOFT developers:
In BIMx Desktop Viewer it is possible to invert the Mouse direction with the "Mouse Invert" setting.
However, in the BIMx Web Viewer there is no such setting at the moment.
If you set the "Mouse Invert" setting to "YES" in the BIMx Desktop Viewer then the directions will be the same in the Desktop Viewer and the Web Viewer.
Development will consider adding this setting to later versions of the BIMx Web Viewer.
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