Works good unless you use IE. On top of that if you create a form in one Mode you can't edit it in another one. The outputted html is full of gibberish (lots of absolute positioning, inline styles etc) from a developer's point of view. The same gibberish is present in the names of the fields - it's a burden to try to rename all fields when their names are generated randomly, without any type of logic (they're just random characters and numbers). Instead they should have used something more like "text1", "text2". At least support is responsive. The extension however leaves me with a bitter taste, it needs much improvement...
if your site has problems (templates, plugins, modules) there is always something that can happen. But BreezingForms is _working well_ with internet explorer.
You should rather contact the support so we can find out what is wrong with your site:
For the positioning: If you decide to use the classic mode, you will have absolute positioning of elements (it is even mentioned in the feature list). There is nothing bad about it. If you don't like it use the QuickMode, please.