Given the new diary fresh off the presses, it should be possible to build "support-only" divisions, from brigades like anti-tank, AA and so forth. Now, they should have no (or very little) combat value without regular line units present, but they should add their special abilities whenever they are in the same stack (or defending in the same province) with regular units.
However, some of their abilities should still be active - for example, it should be possible to deploy independent AA "divisions" (1-brigade units) to protect key areas.
However, some of their abilities should still be active - for example, it should be possible to deploy independent AA "divisions" (1-brigade units) to protect key areas.