Need help in Support Tactictics and items

No problem! I know what you mean with having to be the ward *****, trust me :D

CM is also my biggest love, and most played hero. If you want give a look at my games, just to get ideas: http://www.dotabuff.com/players/175327573/matches?hero=crystal-maiden

If I have an Urn of Shadows and a Force Staff my CM is usually more than set, OP items saving my scrubs every pub ahah

I always like to see other styles on the heroes I play too, sometimes we get new ideas that we can incorporate in our own plays :)

Don't forget about Glimmer Cape - it's a really useful item for escaping, surviving nukes, landing your ult and helping teams mates - plus it's relatively affordable.

Generally my CM build is - Tranquil Boots -> Urn of Shadows -> Glimmer Cape -> whatever I can afford. You're generally a #4.5 at best on CM, so Wards/Sentries are your responsibility.

BKB / Aghs / Force / Blink / Ghost / etc are great to have, but they're very dependent on getting more than standard farm, or the game going long. CM is actually a good farmer, so pick off big neutrals/camps/waves when nobody else is around to take them, and you're not needed elsewhere.

My bad forgetting that, yea, I also get Glimmer Cape in 90% of games. I prefer to have mobility over Glimmer if possible, but still, it's one of the best items for her.