I noticed that you have the Ask Toolbar included in the setup. However, there's a problem.
If the EXE file called ApnStub.exe can't access the internet due to being blocked by a firewall, ImgBurn setup delays showing. You have to force close ApnStub.exe to get ImgBurn setup to show immediately or wait 2 minutes for APNStub.exe to finally close itself.
I suggest that you make a check box that says intall this item to run the ApnStub.exe, so that it won't interfer with the normal operation of the setup installer. Otherwise, someone who encounters this may think that setup is having issues.