I don't like OA mapvote screen, the fonts are big and everytime I click the arrow to scroll down I have to wait some seconds before it scrolls, sometimes move the pointer in and out and click many times to select a name. Or use keyboard arrows and press enter.
I have noticed that the mouse had problems.
I didn't know why for a long time so I couldn't fix it.
But a few days ago Superbots,Grunt told be that it worked if you pressed "Back" and selected it again... and it does. This gives me an idea on what is wrong.
About the delay on page change... it is a design decision. I only send one mappage at a time meaning that every time you hit an arrow the client will make a call to the server for the next page. The alternative was to send all maps but that could cause problems if the server had too many maps and it would be a waste if the client never wanted to vote for a map change.