'Not solved' as in the Building Part is still touched after recompute? I thought that is already fixed. If you mean the group touched after member modification problem, you can try my branch here. This feature branch starts out as for changing the group and geo group behavior in general. But it has since evolved into a quite significant enhancement in 3D visual and selection. I am about to release it, but still testing right now, and keep having annoying little problems here and there.
The related group behavior change is that only App::DocumentObjectGroup and App::Part will auto touch itself when their children are changed. The reason is that these two types of group will export a compound shape of their visible children. It also affects how these objects behavior when doing STEP export. So touching keeps the exporting shape in sync with the current children.
This behavior is controllable through a new property 'ExportMode' in the group object. The options are 'Disabled' means no touching on child change, 'By Visibility' (default) export only visible children. 'By Query' will inject a property 'Group_Export' into each children object, and export only children with this property set to true. And finally 'Both', means export 'By Query' and 'Visibility'.
Other objects containing GroupExtension (e.g. Building Part, I guess), or GeoFeatureGroupExtension, will by default hide the 'ExportMode' property, and set to 'Disabled' by default. Python code can unhide it and change the default value if desired. End-user can reveal the property and change it, too, by right clicking the property view and choose 'Show all' menu action.