Customize PHP Script For Me (Snippet Manager)

General information for the website: This is a php script to manage snippets, images and templates.
Kind of development: Customization of existing website
Description of requirements/features: I bought a php script from Codecanyon.net that I need to have customized to my needs.

There are a total of 5 things that I need done. Details are below.

You can see the original script demo here: http://microcode.ws/demo/snippets/
Username = admin
Password = admin

#1: Add Functionality To Snippet Manager

For snippets, I need a way to run and output the snippets.  A lot of what I intend to use the script for is to manage all sorts of css snippets.  So I would prefer to be able to view the output, similar to the way they do it on csspop website.  http://www.csspop.com/view/821.  So instead of just adding the css to the script like it works now, I would need the ability to add both html and css, then view the output.  So the end result is it should function very similar to csspop example above in terms of adding both html, css and the script rendering the output.

#2: Images

If you go to add snippet you will see an option to insert an image from a url. I still want the insert image, but instead of doing it from a url I need the ability to upload the image from my computer.  I also need the ability to view all images in an image gallery.  Using the demo script as the example, there is a category called "Images".  So basically what I need is when I view the category "Images", I need to have the ability to see all the images in that category in an image gallery.  I plan on having thousands of images in the script. So clicking on each one to view the image would take too much time to find one I want to use.  An image gallery option would solve this problem. 

#3: Website Template Manager

Basically all I would need done here is a way to upload zip files for all my website templates and upload a screenshot of the design. We often reuse our existing templates on new projects, so the idea here would be to have an easy way for me or a coworker to see a list of all website templates we have saved in the script, and have the option to download the template zip file.  I also have the same problem here as I do with the images.  It will take too much time to click on each individual template to see a screenshot of what the design looks like, so I would need the ability to view all template screenshots in an image gallery. 

#4: Filtering Option

This is pretty straight forward. I just need to have a way to filter the main table. I plan on having thousands of snippets, images and templates in the script. So I would like to be able to easily filter the list by keywords or tags.

#5: Tagging System:

I guess we might need some sort of tagging system for the script too. I would need the ability to create multiple tags for each item.

So for tagging, when I go to add a new snippet, image or website template, I want to be able to tag that item. The idea here is when I am searching for something, I want to easily be able to filter things by common tags. For example if I was trying to find a template to use, I might want to filter only responsive templates. I realize I already can put things in categories, but a tagging system would allow me to tag the item into multiple categories.

In summary, I'm just looking for an simple way to manage all the assets we use in my business.  We have several workers, but they all work from different locations.  So having a script to manage all the assets in my business is what I am shooting for.

Please have a full understanding of the project if you apply for the job. I'm really only interested in working with people who have excellent feedback. I want a robust script that can handle all the above things for me, so I welcome any ideas you might have on better ways to achieve what I am trying to do.
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