Hi Natalie,
> I'm using WAB version 2.5. When i add the version 2.12 Data Aggregation widget it gives the following error:
"Create widget setting page error"
Just to clarify, are you using Web AppBuilder for ArcGIS Developer Edition v2.5 and trying to add a widget that was built on a later release of Web AppBuilder? My guess is the widget may be referencing files/components from a more recent release of the ArcGIS API for JavaScript API and they may be missing in the earlier release.
About release versions—Web AppBuilder for ArcGIS (Developer Edition) | ArcGIS for Developers
FYI, Web AppBuilder v2.5 uses the JavaScript API v3.21 while Web AppBuilder v2.12 uses the JavaScript API v3.28.
I suggest you upgrade your Web AppBuilder for ArcGIS Developer Edition to v2.12.
Hope this helps,
