Can I keep my customizations when I upgrade?

I may have had some file changed by my own error when I first started using Zen cart. Since then, I have used a different template. Will this upgrade over ride the changes made to all except the template? Or will I have complications with this upgrade?

You might want to check out the following article in safely upgrading your ZenCart store while retaining all of your customizations. Is your new template 1.5 compatible? Is an update available for it? If so this will likely save some headaches as the new template can be installed on version 1.5. This would allow you to focus your WinMerge on only the customizations / differences between your present install of ZenCart vs the new 1.5 version. Make sure to backup both your database and all your files before moving forward :)

3 EASY STEPS TO UPGRADE ZEN CART: https://www.zen-cart.com/tutorials/index.php?article=108