umm... Assalamua alaykum sis,
what exactly are you talking about?
that's from TTI? Really ? Where... ? I'm curious, I haven't noticed it.
That was my first point. Second point is to calm down and just think things through with a clear head. If you look back at the thread you were reading from where you seemingly interpreted that it was said that "its not good to make up ur own dua" you might quite well notice that, in truth, that's not what anyone meant.
Of course people make up their own dua. It's narrated that the Sahabah used to make a dua even for a shoelace if it was broken. The making of dua is not ever wrong. Allah mentions that He responds to the Call of the Caller when he calls Him, in many places in the Qur'aan, and Allah actually encourages al of mankind to seek from Him. Therefore that's not what was meant, i think what people only meant to say was that asking other people to make the same dua as you, making it something concrete and solid that is spread, is what is not good. That should only seem right and proper with the Dua's given to us by the Prophet

... but as an individual and at an individual level, there's nothing wrong in it.
wallahu 'alem
wasalam