Hi! I read a suggestion from panaghiotisadam that is very simple and works. I;m not sure if its for multiple images but I try and for one fix image works.
Here is his suggetion:
Create a 950px wide image (height can be as much as you like), upload it via Media > Add New, copy its URL. Then go to Appearance > Theme Options and put your image in the “Welcome Message Content” box this way:
<img style=”margin-left:-.75em;” src=”IMAGE URL HERE” />