Excuse for that I interfere ツ But this theme is very close to me. I can help with the answer. Write in PM. or
Really? or
This question is not clear to me. or
Between us speaking, I would try to solve this problem itself. or
You commit an error. Write to me in PM, we will discuss. or
Good business! or
It has no analogues? or
In it something is and it is excellent idea. It is ready to support you. or
Excuse, that I interfere, there is an offer to go on other way. or
Very similar. or