Need help getting portals fixed

You might compare what you are trying to set up to the examples found in: "Adventures in FileMaking #2 - enhanced value selection". Unlike the starter solutions, these examples come with detailed explanations of how they work and how they were designed. The calculations and scripts include comments--something else that the developers of the starter solutions mysteriously forgot to use.

Purchase Order table : Click Select + Popover, then Have a list of Vendors listed in the portal

And what is the relationship you set up for that portal? To what table? with what match fields? There are a lot of details that have to be exactly correct in order for this type of set up to work. One of the reasons that I recommended that file is that it is much easier to work with than a starter solution and you can compare each of the design details in the Adventures in FileMaking file with your file to see which are different and might explain why your attempt is not working. As a suggestion, I'd set that portal up to list all related records as an initial step and then try adding a "Search" or "filter" capability only after I can get the list of vendors to appear in the portal and set them up so that picking a vendor performs the needed script to correctly update my Purchase Order record.

It is very possible the relationships I've set are not correct.

It IS very possible, but since you have not described your relationships, I cannot confirm or correct that possibility for you.

I've even edit the layout of the Starter Solutions to find if I am missing any scripts, or what. I dont seem to gather much from there. 

The starter solutions are very impressive examples of what is possible in FileMaker but very poor examples to use to learn more about how to do it if you are new to FileMaker and/or relational database design mostly due to a deplorable lack of documentation describing their design and function. That lack of documentation makes them very irritating to work with even when, like me, you are a developer with over 10 years experience working with FileMaker.

This is one of the reasons why I launched the Adventures in FileMaking series which are designed to function as tutorials from the ground up with both instructional content listed on each layout as well as documentation for each field and script built right in.

I would love to send you or someone the file so you can help me fix it in 15 minutes as opposed to be spending 2 days wondering. Let me know if you could help. 

This is called database consulting work and is what I do for a living. I do sometimes help someone out in this fashion through the forum, but it's an act of giving my services away for free. There may, however, be other forum members here willing to take a look at your file so you can always upload a cloned copy (no records) of your file to a file sharing site such as drop box and ask forum members to take a look at it.

You'll need to break that down and tackle one of these at a time. You may even want to start new threads on some of them.

But listing the tables does not document your relationships. Knowing how each table links to another and by what match field is crucial to anyone understanding your current design and suggesting any needed changes.

You can upload a screen shot of your relationships using the Upload an Image controls below Post a New Answer or you can use text notation such as:

Parent----<Child

Parent::__pkParentID = Child::_fkParentID

For an explanation of the notation that I am using in the lines above, see the first post of: Common Forum Relationship and Field Notations Explained

We seem to be discussing the same thing in two threads. I asked a key question in the other thread that I need an answer for before proceeding with any of these issues.