There is a problem in IE7 and the Popups API module when in RTL mode.
The loading gif apears and the popups overlay too, then the screen gets very wide (horizontal scrolling) and no popup apears.
I tested on a clean install with core themes and very basic modules enabled.
No problem with other browsers.
I would give more info but I don't know where to start...
This is a very important module.
any help will be appreciated.