Please help upgrade newb

[Miff]

okay so im new to zen cart and brand new to upgrading. basically I have built my most recent store using 1.3.9g and as many know there were quite a few bugs mainly with the html. As mentioned in many of the threads, I have created a whitelist file which has eradicated most of my issues, however when creating a new product, the preview screen which appears before final confirmation, seems to still not read html but instead shows exactly how you have coded, tags and all. Whilst looking for a fix for this I noticed that most threads had been updated that fixes are no longer required and that 1.3.9h should be installed.
So... I tried to upgrade following the upgrade readme on the zen website but im completely new to this and am getting seriouse brainache. I do have a few mods and have edited a few files however Im sure that most of the raw files that I edited were instead copied to a new folder named with my template name, at the same level, instead of overwriting the original. I do still believe that there may be a couple of cases whe I edited the raw files, but only for minor fixes. I have downloaded and tried to use beyond compare 3 and all seems great at first however there are so many files that are in one and not the other, or in both but the same but since im new to merge software I quickly get lost and forget what I am actually looking for with the merging sftware. Can anyone help me with my upgrade hand on, or maybe link me to a more instructive upgrade guide than zens. I realy cannot afford any mistakes but do also need to learn to upgrade for the future. Any help would be appreciated. Thank you

[Miff]

I guess I'm not the only one then!

[kobra]

Maybe this?
https://www.zen-cart.com/tutorials/i...hp?article=108

[stevesh]

I have to say that upgrading from one 1.3.9 version to another isn't nearly as complicated as that tutorial describes.

Just look in the /docs folder and open changelog-v1-3-9h.html. Copy the files that are listed as having been changed from your unzipped 1.3.9h zip file to your remote server, overwriting what's there.

Most, if not all, of the files changed are system files and are unlikely to have been modified in your site's files, unless you've made a point of fiddling with core files.

[saitomedia]

Which mods did you installed along side your Zen Cart installation? Please list.

I'm sorry if this question is nonconstructive, but imo, it matters. Ignore this post if it's insignificant.