You are going the have to give us A LOT more details here….
Have you installed the Google fonts using Main Options > Fonts & Custom > Weaver Xtreme Plus Fonts control, following Step one and two?
Did that work, and does the font show up in the list of available font Below Step 2 > Remove added fonts?
Does the font show inside every theme text property > Family font drop down list?
Is the font installed properly as detailed above, but not show up when selected in a theme Text property Family option?
If so what is the font name, give us a link to the page with details of what text to look at and where.