Go to Post Action and select the action you want. This'll make the error page appear.

Then simply scroll down to the Preview/Submit buttons. Press Preview. You should then see the error: "There were one or more errors processing your request". However, if you scroll down a smidgen, you'll see something interesting.

You can now select the specific options of the dice/numbers in the chosen "Post Action." From there you can select what you want the action to do and then, when you're done writing your post, press submit. It's just hitting preview to cancel out the URL issue.

- By Humbra

(Thank you once again Humbra for your assistance. ^_^)