Man,
1.- My board is set for 2 languages but my fellow forumers there are mostly spanish speaking ppl. The way the original bridge file shows the date it goes like this, for example February 25, 2011.
As I don´t need to have the month to be shown in english, so in the bridge I changed whatever it was on there into this:
$rss->date_format = 'm-d-Y g:i:s A'; //date format of RSS
So I have numeric month, but honestly I don´t think this has something to do with IE.
2.- If you plugin is active, in your header template you should have {$ajaxticker} somewhere in there. Just remove that from there and save the file. Then go to your index template and paste it above where it says {$forums} and save it. I´m not sure if this has something to do with IE, all I know is that the ticker loads only at index instead of every single page of the board minimazing server performance.
My current Mybb version is 1.6.2 and yes, i can send you the bridge file if you give me some email address or if you enable PM messaging here.