You don't need to be a member of the PC to post pictures, I just test posted a 1600 x 1100 jpg, and it works fine, it just takes some futzing around to get it to show.
If you are signed in, and you click on "Gallery", you get to which has headings "Photo Gallery" then "Members Gallery"(which is in a tan rectangle). If you click on "Member's Gallery" you will be taken to the members gallery, but you won't see the picture that you saw on the previous page. On the "Member's Gallery" page, you will see a grey box on the right side that says "New Image." If you click on this box and upload a picture, you will get the situation I just described. Why, I don't know.
In order for the pics to ACTUALLY appear in the gallery, you must add them to an album first, then you must make sure that that album is a PUBLIC album.
1. When you are signed in, click on your avatar picture in the top right corner. This takes you to a page called "Spring's profile."
2. On the right of the page, there is a grey box labelled " Edit my Profile." click that. It takes you to a page called "Your Options."
3. Under the caption "Your Options" you will see four headings, click on the rightmost heading, "Gallery."
4. You will see a caption "No Albums Found
Click here to create your first album! " Click that to create an album.
5. You will see essentially the same page as before, except now it will have Album parameters to edit, like "album name","album description," "Category," and the most important one "
Public Album - Checking this box will allow other users to view your album."
Check this box to have your pics visible in the member's gallery, and to put them in posts.
6. Click on the black "Create album" button at the bottom of the page. This creates the album and allow you to add pictures, delete them, etc.
7. You should now be at the page in your profile which has an "Album Manager" heading in a tan rectangle. Under that, you should see the album name that you created, status,(It should say "Public") , category,Stats, and then "Controls." Under "controls," there should be a drop down menu box labelled "Select an operation." If you click the down arrow, it will give you options" edit, delete, view, new image, new media."
8.If you click on "New image" ,you can add pictures to this album, and they can be seen in the member's gallery. I think you have used this page before, so you know how to do that.
9. Now when you add an image to the album, a page will open with the picture title at the top, and a tan rectangle on the right,
with the heading "Image Details". It's here that you should see all your image properties. Under this box is an often missed little box, called "mod options", in grey. If you click on that, you can edit, move, or delete your image.
Phew! that's alot of work just to get a picture up, I must say. It's one of the hardest procedures to get pictures posted on a public board that I have seen, it's so circuitous.
Sorry for all the words, but it might help. I posted a picture, "Footvase.jpg" just to make sure it works.
You can get it to work too!