I can not recreate an problem removing an attachment. Can you provide specific information regarding what you were attempting to do, including which post you were trying to edit and which attachment you were trying to remove.
Recent topics "holds your place," so it will go back to the last page you were looking at. Try using the "Start" link in the bread crumbs at the top and bottom of the page to go back to page 1.
I probably haven't been on page 2 for years or at least months so I definitely wasn't reading it. I tried hitting Start just now to go back to page 1 then went to Recent Topics again and it brought me to page 3 which I definitely wasn't on. I guess its just me so I'll deal with it for now.
On a separate note, the site logs me out each day. I can’t be sure, but it feels like if I visit the site on my phone, I have to log back in on my PC when I get home, as well as my iPad, and then the following day I have to log back in on my phone, repeat. But it might just be the timing as my routine is pretty similar each day.
Since you modernized the site I have one problem: Most incoming links into the site, including the first result in google load some weird google caché instead of the actual website. For example:
If I load that link on my PC, it does redirect me into the normal version of the website but the redirection does not work on my phone (iOS) and makes the site barely useable.