IE browser does have ‘pop up blocker’ settings that you may need to review. it is possible that the ‘default’ setting is to block everything.
in terms of printing in firefox.. not anything we’ve heard or seen before to be honest. Please raise via the support ticket attaching your form, details of what this ‘trouble’ is and any detail required if there are specific steps required running your form to be able to print and we can look into it.
PS.. also note what version of firefox you are using.. there have been a few updates recently in firefox so worth confirming you are running the latest