So, I've got the Bethesda release of Arena. It was working fine, then I decided to try the 1.07 version. There is a patch on UESP that upgrades it. It seemed to work, but now I can't figure out how to get it to run.

I'm pretty sure it's just my ignorance of DOSBox that's causing the problem. I've been launching it from a shortcut leading to a config file like it says on here, but that's no longer working.

Has anyone used the UESP patch that can tell me what I'm doing wrong?

There is no 1.07 patch.

1.06 is the latest floppy version, which was released for free back in 2004.
1.07 is the CD version, which has not been released for free.

It's user-made, got it from the Unofficial Elder Scrolls Pages. Go to Arena:Files, it's there. Sadly I can't link to it.

I see. Discussions about fanmade patches filled with pirated content aren't really a good thing.