Regarding your issue with IE9, Qlik Sense does support only Internet Explorer 10+,as mentioned here: http://help.qlik.com/sense/2.0/en-us/developer/#Introduction/supported-browsers.htm?Highlight=internet explorer
mwegmann: can you post your code, so we can have a deeper look?
Take a look at qlik.resize(). You might need to call it in your mashup, specially if you do something more advanced, like resize the elements your Qlik objects are in or hide and show them.
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