They make it so hard to get your desired ending. I played the last mission thinking I could put NCR in control. In comes Gen. Oliver. Hey look at the options... nothing telling YesMan to stand down. Nothing about putting the NCR in control. Its really ruins the plot!!!! Fallout3 ran sooo smoothly. Then this is just, weird.
I still don't know how to put the NCR in control...

You worked with Yesman, so the NCR wouldn't be in control. You have to do the questline "For the Republic" in order to put NCR in control.

Edit:

I only found the NCR embassy after i finished the quest twice...

Its opposite the vault, 21 i think. The one under the Strip

EDIT: yep i was right you then go and see ambassdor crocker. I would have been useful to add the quest when your apporached by the guy so a quest marker shows you where the embassy is :shrug:

There's 4 different main paths. If you wanted the NCR in power you had to side with the NCR.

It's not about getting your desired ending, it's about seeing how your actions changed the wastes.
So what you do will have influence on the ending sliders.
If you decide to do something for someone that works towards NCR then it's your own fault for NCR coming short in that area.
So for future playthroughs think about what you're going to do and what consequences it might have before you take action.

Ya, I encountered the same problem with the ending, but I had to take the wild card route because the NCR quest-line was bugged due to me already talking the khans into fighting for the NCR before I started the NCR chain..... made me frustrated that I could not complete the first quest.

I know all that. But you need the options of your words to. I helped the NCR all through the game. It would of been easy to just say. "Your welcome sir, ill call of the securitrons now"

And I could never go to the dam after Crocker told me to because it was glitched and everyone was still walking around like when the Pres was almost asasinated. :spotted owl:

Agreed. The Wildcard path could have had the option to combine with NCR and perhaps Legion. Especially Science characters could have reprogrammed Yes-Man to be more NCR-friendly. The player should be able to negotiate a governorship over Vegas or something. Free army? Why yes please.

lol