Hi again
Here's detail instructions:
1) Go to template manager, select gk_fashion template and click on "duplicate"
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2) You now have gk_fashion 2 . Click on this template to change parameters.
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3) On gk_fashion 2 parameters, go to menu options and select the menu that you want to display on this template. For my example i will use "Categories menu"
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4) Go to "Menus > Mainmenu" and to create a new link that will be used to "jump" from gk_fashion to gk_fashion 2. Actually i will called "Jumplink"
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5) On the "Jumplink" menu parameters, set template style to gk_fashion 2 and save.
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6) Open frontpage and now you will see the "Jumplink" on mainmenu. Click on this link and see what happens
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7) You now have "Categories Menu" instead of "MainMenu".
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You can do the same on "Categories Menu" by creating a new Jumplink to return to "Mainmenu" menu that uses gk_fashion template.
That's it