Hi,
I read your question and I test your website with IE/Firefox/Chrome.
The only thing that I can say you is that, your template is not right compatible with all browser.
Yes, the look in IE and in Firefox/Chrome is not the same. It can't say you why but the problem does not come from the HikaShop module.
You can put whaterever you want in the module, his content will be displayed "inline" in IE and in several lines in Firefox/Chrome.
Yes, it is just a little module in the position in your template. Nothing tricky.. For what I saw, it is just a template design problem.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.