I have stuck in a very simple problem, I am using Windws instaler to deploy my project.
In that I have used a custom dialog [TextBoxes(A)] for User name and Passowrd.

Now what I am trying is two things
first to Enable Next button on the dialog only if user enters both values i.e. Usename and Pwd and second as user click Next followed by filling both fields a validation should occue(I have code ready in c# for validation!), I validate user can go to next dialog in Installer.

I tried some stuffs with Orca but I didnt succed, please help me in providing the solution.