Hey, i hope u'll be fine.
we have read and understand your requirements
This is really very simple job, I'll create an extension that will allow user to upload logo and provide user an area where he can modify his image, javascript files can also be used from your example site.
Here i am going to attach my example magento extension, that adds an attribute to product settings in admin and then adds its first image in a gallery. this is to show you my work i've done for a local company.
We want to win best score and remarks from you, We'll work hard to provide you exactly what you want.
Thanks,