I need Your help with extrusion. Can't figure out how to extrude something like window frames on a spheric surface and make them solid, while window surfaces must remain flat. When I extrude faces along normals, then it solidifies my window surface as shown in the screenshot 2 below. Basically, I want to extrude windows frames simultaneously inward sphere and outward sphere. How can I achieve that? Thank You!
Use "separate objects" when in edit mode and you have the window panes selected. Put them in a separate grouping. Then tab out of edit mode, use solidify on the frame, and not on the panes group. Parent the panes to the frame for scale adjustments as "parent object" in object mode, select panes-object first, shift+click frame and apply parenting (right click or menu etc). The panes will have the thin non-solidified thickness and the frame will still have a solidify you apply, adjust as required.