renwing, I had this same problem (question #1) myself when I started--do you have just the "Default" journal or do you have others too? I found that I couldn't add anything to the "Default" journal, but when I created a new journal called Garden 2005 I had no trouble adding things to it instead. Here is a link to a thread where I helped someone else out with this same problem (this is a long thread with lots of other topics--look for the exchange of posts between me and MollyMc beginning on Sep 17 of this year): http://davesgarden.com/forums/t/251387/
For question #2, if you are able to successfully import a plant into your journal from PF, the link will automatically be there (most of the time at least--I've run into a few where for some reason there is no link). If it's a plant that you already have in your journal and added it manually vs importing from PF then I don't know of a way to add a link (other than importing it from PF to create a new entry and deleting the old one). But I'm pretty new here, so there may be a way to do this and I just don't know it yet.
If you don't choose a category to put the plant in when you import it, then it gets put into your "Unknown" status, so if you want to find the plants you've imported you need to go to the section for Access by Status and choose Unknown, and all your plants should be there.
If you want to find them easier in your journal, after you import the plant you can choose to put it in one of your categories--the screen you see where it tells you the plant has been added should also say "click here to choose a category", if you click that it should bring up a list of all the categories in your journal and you can choose one to put it in, once you do that then it is easier to spot it in the journal.
GAHH! Okay, it is importing and that is wonderful!
But now its importing into the journal I don't select! I select the journal I want it in and then the category and it puts it in the right category, but the wrong journal. Then it gets weirder. When you look at my journal home page, It shows the journals with the number next to them indicating the number of items in the journal. It shows the correct number. But when you click on that journal, nothing is there but categories! Then I click on my other journal were there shouldn't be any entries and they are all there!
I think I know what's going on--before you import your plants, go to your journal page and in the section called Change Your Default Journal make sure you've selected the journal you're planning to import to. For some reason the program wants to add the plants to the journal you've selected on your main Journal page, regardless of what journal you tell it to use when you're importing. I just tried an experiment with my journals where I selected my "Garden 2005" journal on the journal page, then I went to plant files and told it to import a file to my "Wish List" journal, then when I went to look for the plant sure enough it was in my Garden 2005 journal even though I told it to put it in the other one. Hope that helps!
I don't know about being a guru--I just happened to figure out this one feature of importing plants into my journal (after many hours of trial and error!) But if you asked me how to do anything else in the journal, I'd be absolutely useless!