These sound like relationship issues for the most part. There may be additional layout issues as well.
Might you have these relationships?
If so, a record in internal can't show in your portal until a record in External is created that "connects" it to your layout's current record.
For 3, it sounds like you may have a "delete" option enabled for external in the internal to external relationship.
These are just guesses. Other issues may be the cause. Describe your relationships and how you have set up your portals.
It would be better to post a screen shot from Manage | Database | Relationships. Sometimes the theoretical relationships don't match what actually gets set up in the file. It also provides the actual table occurrence names that you should be using to set up layout and portals.
I also asked you to describe how you have set up your portals. Put your layout into layout mode, capture a screen shot that shows the portals and the name of your layout in the status area in the top left portion of the window. Use the view menu to make sure that "sample data" is not enabled so that the fields' names are visible instead of sample data. Share that screen shot here.
Also, if you have set up any portal filters, please describe them as well.
I rechecked and I found the mistakes in the portal setup.